Compound and light-emitting device including same

ABSTRACT

A compound for a light emitting device, the compound being represented by Formula 1:wherein, in Formula 1, the variables are defined herein.

CROSS-REFERENCE TO RELATED APPLICATION

This application claims the benefit of Korean Patent Application No. 10-2020-0023839, filed on Feb. 26, 2020, in the Korean Intellectual Property Office, the disclosure of which is incorporated herein in its entirety by reference.

BACKGROUND Field

Exemplary implementations of the invention relate generally to a compound and, and more specifically, to a light-emitting device including the compound.

Discussion of the Background

Light-emitting devices are self-emission devices that, as compared with conventional devices, have wide viewing angles, high contrast ratios, short response times, and excellent characteristics in terms of brightness, driving voltage, and response speed.

Light-emitting devices may include a first electrode on a substrate, and a hole transport region, an emission layer, an electron transport region, and a second electrode sequentially stacked on the first electrode. Holes provided from the first electrode may move toward the emission layer through the hole transport region, and electrons provided from the second electrode may move toward the emission layer through the electron transport region. Carriers, such as holes and electrons, recombine in the emission layer to produce excitons. These excitons transit from an excited state to a ground state to thereby generate light.

The above information disclosed in this Background section is only for understanding of the background of the inventive concepts, and, therefore, it may contain information that does not constitute prior art.

SUMMARY

Light emitting devices constructed according to the principles and exemplary implementations of the invention include a compound having a novel structure that provides for decreased driving voltage, improved efficiency, and increased half lifespan.

Additional features of the inventive concepts will be set forth in the description which follows, and in part will be apparent from the description, or may be learned by practice of the inventive concepts.

According to one aspect of the invention, a compound for a light emitting device, the compound being represented by Formula 1:

wherein, in Formula 1, the variables are defined herein.

The variables R₁₅ and R₁₆ may each, independently from one another, be hydrogen or deuterium.

The two adjacent substituents of R₁ to R₁₄ and R₂₁ to R₂₃ may be linked to each other to form a ring.

The variables X₂ and X₃ may each, independently from one another, be O, S, or NR₂₁.

The variables X₁ and X₄ may each, independently from one another, be O, NR₂₁, or CR₂₂R₂₃.

The variables R₁ to R₁₄ and R₂₁ to R₂₃ may each, independently from one another, be hydrogen, deuterium, a substituted or unsubstituted C₁-C₆₀ alkyl group, or a moiety represented by one of Formulae 2a to 2g, as defined herein.

Two adjacent substituents of R₁ to R₁₄ and R₂₁ to R₂₃ may be linked to each other to form a ringed moiety of Formula A, as defined herein.

Two adjacent substituents of R₁ to R₁₄ and R₂₁ to R₂₃ may be linked to each other to form a ringed moiety of Formula B, as defined herein.

The compound represented by Formula 1 is one of the Compounds 1-32 as defined herein.

A light-emitting device may include: a first electrode; a second electrode facing the first electrode; an interlayer between the first electrode and the second electrode, the interlayer including an emission layer; and a capping layer having a refractive index of about 1.6 or higher, and wherein the interlayer may include the compound defined above.

The emission layer may include a fluorescence emission layer.

The emission layer may include the compound.

The emission layer may include the compound as a host.

The emission layer may include the compound as a dopant.

The emission layer may include a phosphorus-containing compound as a host and the compound as a dopant.

The compound may be a thermally activated delayed fluorescence material.

The first electrode may be an anode; the second electrode may be a cathode; and the interlayer may include i) a hole transport region between the first electrode and the emission layer, the hole transport region may include a hole injection layer, a hole transport layer, a buffer layer, an electron blocking layer, or any combination thereof and ii) an electron transport region between the emission layer and the second electrode, the electron transport region may include a hole blocking layer, an electron transport layer, an electron injection layer, or any combination thereof.

The emission layer may include one phosphorus-containing compound as a host and the compound as a dopant; and the electron transport region may include another phosphorus-containing compound.

The one phosphorus-containing compound and the other phosphorus-containing compound may be the same compound.

An electronic apparatus may include: a thin film transistor and the light-emitting device as defined above, wherein the thin film transistor may include a source electrode, a drain electrode, an activation layer, and a gate electrode, and the first electrode of the light-emitting device may be electrically connected to one of the source electrode and the drain electrode of the thin-film transistor

It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory and are intended to provide further explanation of the invention as claimed.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings, which are included to provide a further understanding of the invention and are incorporated in and constitute a part of this specification, illustrate exemplary embodiments of the invention, and together with the description serve to explain the inventive concepts.

FIG. 1 is a schematic cross-sectional diagram of an exemplary embodiment of an organic light-emitting device constructed according to principles of the invention.

DETAILED DESCRIPTION

In the following description, for the purposes of explanation, numerous specific details are set forth in order to provide a thorough understanding of various exemplary embodiments or implementations of the invention. As used herein “embodiments” and “implementations” are interchangeable words that are non-limiting examples of devices or methods employing one or more of the inventive concepts disclosed herein. It is apparent, however, that various exemplary embodiments may be practiced without these specific details or with one or more equivalent arrangements. In other instances, well-known structures and devices are shown in block diagram form in order to avoid unnecessarily obscuring various exemplary embodiments. Further, various exemplary embodiments may be different, but do not have to be exclusive. For example, specific shapes, configurations, and characteristics of an exemplary embodiment may be used or implemented in another exemplary embodiment without departing from the inventive concepts.

Unless otherwise specified, the illustrated exemplary embodiments are to be understood as providing exemplary features of varying detail of some ways in which the inventive concepts may be implemented in practice. Therefore, unless otherwise specified, the features, components, modules, layers, films, panels, regions, and/or aspects, etc. (hereinafter individually or collectively referred to as “elements”), of the various embodiments may be otherwise combined, separated, interchanged, and/or rearranged without departing from the inventive concepts.

The use of cross-hatching and/or shading in the accompanying drawings is generally provided to clarify boundaries between adjacent elements. As such, neither the presence nor the absence of cross-hatching or shading conveys or indicates any preference or requirement for particular materials, material properties, dimensions, proportions, commonalities between illustrated elements, and/or any other characteristic, attribute, property, etc., of the elements, unless specified. Further, in the accompanying drawings, the size and relative sizes of elements may be exaggerated for clarity and/or descriptive purposes. When an exemplary embodiment may be implemented differently, a specific process order may be performed differently from the described order. For example, two consecutively described processes may be performed substantially at the same time or performed in an order opposite to the described order. Also, like reference numerals denote like elements.

When an element, such as a layer, is referred to as being “on,” “connected to,” or “coupled to” another element or layer, it may be directly on, connected to, or coupled to the other element or layer or intervening elements or layers may be present. When, however, an element or layer is referred to as being “directly on,” “directly connected to,” or “directly coupled to” another element or layer, there are no intervening elements or layers present. To this end, the term “connected” may refer to physical, electrical, and/or fluid connection, with or without intervening elements. Further, the D1-axis, the D2-axis, and the D3-axis are not limited to three axes of a rectangular coordinate system, such as the x, y, and z-axes, and may be interpreted in a broader sense. For example, the D1-axis, the D2-axis, and the D3-axis may be perpendicular to one another, or may represent different directions that are not perpendicular to one another. For the purposes of this disclosure, “at least one of X, Y, and Z” and “at least one selected from the group consisting of X, Y, and Z” may be construed as X only, Y only, Z only, or any combination of two or more of X, Y, and Z, such as, for instance, XYZ, XYY, YZ, and ZZ. As used herein, the term “and/or” includes any and all combinations of one or more of the associated listed items.

Although the terms “first,” “second,” etc. may be used herein to describe various types of elements, these elements should not be limited by these terms. These terms are used to distinguish one element from another element. Thus, a first element discussed below could be termed a second element without departing from the teachings of the disclosure.

Spatially relative terms, such as “beneath,” “below,” “under,” “lower,” “above,” “upper,” “over,” “higher,” “side” (e.g., as in “sidewall”), and the like, may be used herein for descriptive purposes, and, thereby, to describe one elements relationship to another element(s) as illustrated in the drawings. Spatially relative terms are intended to encompass different orientations of an apparatus in use, operation, and/or manufacture in addition to the orientation depicted in the drawings. For example, if the apparatus in the drawings is turned over, elements described as “below” or “beneath” other elements or features would then be oriented “above” the other elements or features. Thus, the exemplary term “below” can encompass both an orientation of above and below. Furthermore, the apparatus may be otherwise oriented (e.g., rotated 90 degrees or at other orientations), and, as such, the spatially relative descriptors used herein interpreted accordingly.

The terminology used herein is for the purpose of describing particular embodiments and is not intended to be limiting. As used herein, the singular forms, “a,” “an,” and “the” are intended to include the plural forms as well, unless the context clearly indicates otherwise. Moreover, the terms “comprises,” “comprising,” “includes,” and/or “including,” when used in this specification, specify the presence of stated features, integers, steps, operations, elements, components, and/or groups thereof, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and/or groups thereof. It is also noted that, as used herein, the terms “substantially,” “about,” and other similar terms, are used as terms of approximation and not as terms of degree, and, as such, are utilized to account for inherent deviations in measured, calculated, and/or provided values that would be recognized by one of ordinary skill in the art.

Various exemplary embodiments are described herein with reference to sectional and/or exploded illustrations that are schematic illustrations of idealized exemplary embodiments and/or intermediate structures. As such, variations from the shapes of the illustrations as a result, for example, of manufacturing techniques and/or tolerances, are to be expected. Thus, exemplary embodiments disclosed herein should not necessarily be construed as limited to the particular illustrated shapes of regions, but are to include deviations in shapes that result from, for instance, manufacturing. In this manner, regions illustrated in the drawings may be schematic in nature and the shapes of these regions may not reflect actual shapes of regions of a device and, as such, are not necessarily intended to be limiting.

Unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this disclosure is a part. Terms, such as those defined in commonly used dictionaries, should be interpreted as having a meaning that is consistent with their meaning in the context of the relevant art and should not be interpreted in an idealized or overly formal sense, unless expressly so defined herein.

The compound constructed according to the principles and an exemplary embodiment of the invention may have a structure represented by Formula 1:

-   -   wherein, in Formula 1,     -   X₁ to X₄ may each independently be O, S, NR₂₁, or CR₂₂R₂₃,     -   R₁ to R₁₆ and R₂₁ to R₂₃ may each independently be selected from         hydrogen, deuterium, a substituted or unsubstituted C₁-C₆₀ alkyl         group, a substituted or unsubstituted C₂-C₆₀ alkenyl group, a         substituted or unsubstituted C₂-C₆₀ alkynyl group, a substituted         or unsubstituted C₁-C₆₀ alkoxy group, a substituted or         unsubstituted C₃-C₁₀ cycloalkyl group, a substituted or         unsubstituted C₁-C₁₀ heterocycloalkyl group, a substituted or         unsubstituted C₃-C₁₀ cycloalkenyl group, a substituted or         unsubstituted C₁-C₁₀ heterocycloalkenyl group, a substituted or         unsubstituted C₆-C₆₀ aryl group, a substituted or unsubstituted         C₆-C₆₀ aryloxy group, a substituted or unsubstituted C₆-C₆₀         arylthio group, a substituted or unsubstituted C₁-C₆₀ heteroaryl         group, a substituted or unsubstituted monovalent non-aromatic         condensed polycyclic group, a substituted or unsubstituted         monovalent non-aromatic condensed heteropolycyclic group,         —Si(Q₁)(Q₂)(Q₃), —N(Q₁)(Q₂), —P(Q₁)(Q₂), —C(═O)(Q₁),         —S(═O)₂(Q₁), and —P(═O)(Q₁)(Q₂), wherein adjacent substituents         in R₁ to R₁₆ and R₂₁ to R₂₃ may be linked to each other to form         a ring, and     -   at least one substituent of the substituted C₁-C₆₀ alkyl group,         the substituted C₂-C₆₀ alkenyl group, the substituted C₂-C₆₀         alkynyl group, the substituted C₁-C₆₀ alkoxy group, the         substituted C₃-C₁₀ cycloalkyl group, the substituted C₁-C₁₀         heterocycloalkyl group, the substituted C₃-C₁₀ cycloalkenyl         group, the substituted C₁-C₁₀ heterocycloalkenyl group, the         substituted C₆-C₆₀ aryl group, the substituted C₆-C₆₀ aryloxy         group, the substituted C₆-C₆₀ arylthio group, the substituted         C₁-C₆₀ heteroaryl group, the substituted monovalent non-aromatic         condensed polycyclic group, and the substituted monovalent         non-aromatic condensed heteropolycyclic group may be selected         from:     -   deuterium (-D), —F, —Cl, —Br, —I, a hydroxyl group, a cyano         group, a nitro group, an amidino group, a hydrazino group, a         hydrazono group, a C₁-C₆₀ alkyl group, a C₂-C₆₀ alkenyl group, a         C₂-C₆₀ alkynyl group, and a C₁-C₆₀ alkoxy group;     -   a C₁-C₆₀ alkyl group, a C₂-C₆₀ alkenyl group, a C₂-C₆₀ alkynyl         group, and a C₁-C₆₀ alkoxy group, each substituted with at least         one selected from deuterium, —F, —Cl, —Br, —I, a hydroxyl group,         a cyano group, a nitro group, an amidino group, a hydrazino         group, a hydrazono group, a C₃-C₁₀ cycloalkyl group, a C₁-C₁₀         heterocycloalkyl group, a C₃-C₁₀ cycloalkenyl group, a C₁-C₁₀         heterocycloalkenyl group, a C₆-C₆₀ aryl group, a C₆-C₆₀ aryloxy         group, a C₆-C₆₀ arylthio group, a C₁-C₆₀ heteroaryl group, a         monovalent non-aromatic condensed polycyclic group, a monovalent         non-aromatic condensed heteropolycyclic group,         —Si(Q₁₁)(Q₁₂)(Q₁₃), —N(Q₁₁)(Q₁₂), —P(Q₁₁)(Q₁₂), —C(═O)(Q₁₁),         —S(═O)₂(Q₁₁), and —P(═O)(Q₁₁)(Q₁₂);     -   a C₃-C₁₀ cycloalkyl group, a C₁-C₁₀ heterocycloalkyl group, a         C₃-C₁₀ cycloalkenyl group, a C₁-C₁₀ heterocycloalkenyl group, a         C₆-C₆₀ aryl group, a C₆-C₆₀ aryloxy group, a C₆-C₆₀ arylthio         group, a C₁-C₆₀ heteroaryl group, a monovalent non-aromatic         condensed polycyclic group, and a monovalent non-aromatic         condensed heteropolycyclic group;     -   a C₃-C₁₀ cycloalkyl group, a C₁-C₁₀ heterocycloalkyl group, a         C₃-C₁₀ cycloalkenyl group, a C₁-C₁₀ heterocycloalkenyl group, a         C₆-C₆₀ aryl group, a C₆-C₆₀ aryloxy group, a C₆-C₆₀ arylthio         group, a C₁-C₆₀ heteroaryl group, a monovalent non-aromatic         condensed polycyclic group, and a monovalent non-aromatic         condensed heteropolycyclic group, each substituted with at least         one selected from deuterium, —F, —Cl, —Br, —I, a hydroxyl group,         a cyano group, a nitro group, an amidino group, a hydrazino         group, a hydrazono group, a C₁-C₆₀ alkyl group, a C₂-C₆₀ alkenyl         group, a C₂-C₆₀ alkynyl group, a C₁-C₆₀ alkoxy group, a C₃-C₁₀         cycloalkyl group, a C₁-C₁₀ heterocycloalkyl group, a C₃-C₁₀         cycloalkenyl group, a C₁-C₁₀ heterocycloalkenyl group, a C₆-C₆₀         aryl group, a C₆-C₆₀ aryloxy group, a C₆-C₆₀ arylthio group, a         C₁-C₆₀ heteroaryl group, a monovalent non-aromatic condensed         polycyclic group, a monovalent non-aromatic condensed         heteropolycyclic group, —Si(Q₂₁)(Q₂₂)(Q₂₃), —N(Q₂₁)(Q₂₂),         —P(Q₂₁)(Q₂₂), —C(═O)(Q₂₁), —S(═O)₂(Q₂₁), and —P(═O)(Q₂₁)(Q₂₂);         and     -   —Si(Q₃₁)(Q₃₂)(Q₃₃), —N(Q₃₁)(Q₃₂), —P(Q₃₁)(Q₃₂), —C(═O)(Q₃₁),         —S(═O)₂(Q₃₁), and —P(═O)(Q₃₁)(Q₃₂),

wherein Q₁ to Q₃, Q₁₁ to Q₁₃, Q₂₁ to Q₂₃, and Q₃₁ to Q₃₃ may each independently be selected from hydrogen, deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an amidino group, a hydrazino group, a hydrazono group, a C₁-C₆₀ alkyl group, a C₂-C₆₀ alkenyl group, a C₂-C₆₀ alkynyl group, a C₁-C₆₀ alkoxy group, a C₃-C₁₀ cycloalkyl group, a C₁-C₁₀ heterocycloalkyl group, a C₃-C₁₀ cycloalkenyl group, a C₁-C₁₀ heterocycloalkenyl group, a C₆-C₆₀ aryl group, a C₁-C₆₀ heteroaryl group, a monovalent non-aromatic condensed polycyclic group, a monovalent non-aromatic condensed heteropolycyclic group, a biphenyl group, and a terphenyl group.

When a boron atom is added, highest occupied molecular orbital (HOMO)/lowest unoccupied molecular orbital (LUMO) separation between crosslinked atoms may be further enlarged, in other words, “short range charge transfer (CT)” may occur. When it is possible a molecular plane is widely fused, delocalization may be enlarged, polarizability may be increased, and the f (oscillator strength) value may be further increased to thereby achieving a high efficiency when manufacturing devices.

The structure of Formula 1 according to one or more exemplary embodiments may be a polycyclic aromatic compound including two boron atoms and have a planar backbone to thereby easily activate multiple resonance. The compound of Formula 1 according to one or more exemplary embodiments may further activate multiple resonance to thereby have a higher f value and a lower ΔE_(ST), thus further improving thermally activated delayed fluorescence (TADF) characteristics.

In an exemplary embodiment, R₁₅ and R₁₆ may each independently be hydrogen or deuterium.

In some exemplary embodiments, two adjacent substituents of R₁ to R₁₄ and R₂₁ to R₂₃ may be linked to each other to form a ring.

In some exemplary embodiments, X₂ and X₃ may each independently be O, S, or NR₂₁.

In some exemplary embodiments, X₁ and X₄ may each independently be O, NR₂₁, or CR₂₂R₂₃.

In some exemplary embodiments, R₁ to R₁₄ and R₂₁ to R₂₃ may each independently be hydrogen, deuterium, a substituted or unsubstituted C₁-C₆₀ alkyl group, or a compound represented by one of Formulae 2a to 2g:

-   -   wherein, in Formulae 2a to 2g, R₃₁ to R₄₀ may each independently         be hydrogen, deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a         cyano group, a nitro group, an amino group, an amidino group, a         hydrazine group, a hydrazone group, a carboxylic acid group or a         salt thereof, a sulfonic acid group or a salt thereof, a         phosphoric acid group or a salt thereof, a C₁-C₂₀ alkyl group, a         C₁-C₂₀ alkoxy group, a phenyl group, a biphenyl group, a         terphenyl group, a naphthyl group, a fluorenyl group, a         spiro-bifluorenyl group, a benzofluorenyl group, a         dibenzofluorenyl group, a phenanthrenyl group, an anthracenyl         group, a pyrenyl group, a chrysenyl group, a pyridinyl group, a         pyrazinyl group, a pyrimidinyl group, a pyridazinyl group, a         quinolinyl group, an isoquinolinyl group, a quinoxalinyl group,         a quinazolinyl group, a carbazolyl group, a dibenzofuranyl         group, a dibenzothiophenyl group, a triazinyl group, a         benzimidazolyl group, and a phenanthrolinyl group,     -   a31 to a34 and a38 to a40 may each independently be an integer         from 1 to 5, a35 may be an integer from 1 to 7, a36 and a37 may         each independently be an integer from 1 to 4, and * indicates a         binding site to an adjacent atom.

In some exemplary embodiments, two adjacent substituents of R₁ to R₁₄ and R₂₁ to R₁₃ may be linked to each other to form ring-type Formula A:

-   -   wherein, in Formula A, Y₁ may be NR₄₂, O, or S, R₄₁ and R₄₂ may         each independently be selected from hydrogen, deuterium, —F,         —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an         amino group, an amidino group, a hydrazine group, a hydrazone         group, a carboxylic acid group or a salt thereof, a sulfonic         acid group or a salt thereof, a phosphoric acid group or a salt         thereof, a C₁-C₂₀ alkyl group, a C₁-C₂₀ alkoxy group, a phenyl         group, a biphenyl group, a terphenyl group, a naphthyl group, a         fluorenyl group, a spiro-bifluorenyl group, a benzofluorenyl         group, a dibenzofluorenyl group, a phenanthrenyl group, an         anthracenyl group, a pyrenyl group, a chrysenyl group, a         pyridinyl group, a pyrazinyl group, a pyrimidinyl group, a         pyridazinyl group, a quinolinyl group, an isoquinolinyl group, a         quinoxalinyl group, a quinazolinyl group, a carbazolyl group, a         dibenzofuranyl group, a dibenzothiophenyl group, a triazinyl         group, a benzimidazolyl group, and a phenanthrolinyl group,     -   a41 may be an integer from 1 to 4, and * and *′ each indicate a         binding site to an adjacent atom.

Ring-type A may be, for example, found among Compounds 23 to 32.

In some exemplary embodiments, two adjacent substituents of R₁ to R₁₄ and R₂₁ to R₂₃ may be linked to each other to form ring-type Formula B:

-   -   wherein, in Formula B, R₄₃ may be selected from hydrogen,         deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a         nitro group, an amino group, an amidino group, a hydrazine         group, a hydrazone group, a carboxylic acid group or a salt         thereof, a sulfonic acid group or a salt thereof, a phosphoric         acid group or a salt thereof, a C₁-C₁₀ alkyl group, a C₁-C₂₀         alkoxy group, a phenyl group, a biphenyl group, a terphenyl         group, a naphthyl group, a fluorenyl group, a spiro-bifluorenyl         group, a benzofluorenyl group, a dibenzofluorenyl group, a         phenanthrenyl group, an anthracenyl group, a pyrenyl group, a         chrysenyl group, a pyridinyl group, a pyrazinyl group, a         pyrimidinyl group, a pyridazinyl group, a quinolinyl group, an         isoquinolinyl group, a quinoxalinyl group, a quinazolinyl group,         a carbazolyl group, a dibenzofuranyl group, a dibenzothiophenyl         group, a triazinyl group, a benzimidazolyl group, and a         phenanthrolinyl group,     -   a43 may be an integer from 1 to 4, and * and *′ each indicate a         binding site to an adjacent atom.

Ring-type B may be, for example, found among Compounds 10, 19, and 21.

In some exemplary embodiments, the compound represented by Formula 1 may be selected from the following compounds 1-32:

For example, Compound 1 may only be included in the interlayer as the compound. In this exemplary embodiment, Compound 1 may be included in the emission layer of the light-emitting device. In some exemplary embodiments, the interlayer may include Compounds 1 and 2 as the compounds. In this exemplary embodiment, Compounds 1 and 2 may be included in the same layer (for example, both Compounds 1 and 2 may be included in an emission layer) or in different layers (for example, Compound 1 may be included in an emission layer, and Compound 2 may be included in an electron transport region).

In some exemplary embodiments, a light-emitting device may include: a first electrode; a second electrode facing the first electrode; an interlayer between the first electrode and the second electrode, the interlayer including an emission layer, the interlayer may include the compound described above. In some exemplary embodiments, the first electrode of the light-emitting device may be an anode, the second electrode of the light-emitting device may be a cathode, the interlayer may further include a hole transport region between the first electrode and the emission layer and an electron transport region between the emission layer and the second electrode, the hole transport region may include a hole injection layer, a hole transport layer, a buffer layer, an electron blocking layer, or any combination thereof, and the electron transport region may include a hole blocking layer, an electron transport layer, an electron injection layer, or a combination thereof.

In some exemplary embodiments, the emission layer may include the compound of Formula 1. In some exemplary embodiments, the emission layer may be a fluorescence emission layer. In some exemplary embodiments, the emission layer may include the compound of Formula 1. In some exemplary embodiments, the emission layer may include the compound of Formula 1 as a host or a dopant.

In some exemplary embodiments, the emission layer may include a phosphorus-containing compound as a host, and the compound of Formula 1 as a dopant. In some exemplary embodiments, the emission layer may include one phosphorus-containing compound as a host, the compound of Formula 1 as a dopant, and the electron transport region may include another phosphorus-containing compound.

In some exemplary embodiments, the phosphorus-containing compound as a host may be identical to the phosphorus-containing compound included in the electron transport region. In some exemplary embodiments, the compound of Formula 1 may be a TADF material.

An electronic apparatus may include: a thin film transistor and the light-emitting device, wherein the thin film transistor may include a source electrode, a drain electrode, an activation layer, and a gate electrode, and the first electrode of the light-emitting device may be electrically connected to one of the source electrode and the drain electrode of the thin-film transistor.

Description of FIG. 1

FIG. 1 is a schematic cross-sectional diagram of an exemplary embodiment of an organic light-emitting device constructed according to principles of the invention.

The light-emitting device 10 may include a first electrode 110, an interlayer 150, and a second electrode 190. Hereinafter, the structure of the light-emitting device 10, which may be in the form of a near-infrared light-emitting diode according to an exemplary embodiment, and a method of manufacturing the near-infrared light-emitting diode (LED) 10 according to an exemplary embodiment will be described in connection with FIG. 1 .

First Electrode 110

Referring to FIG. 1 , a substrate may be additionally located under the first electrode 110 or above the second electrode 190. The substrate may be a glass substrate or a plastic substrate. The first electrode 110 may be formed by depositing or sputtering, onto the substrate, a material for forming the first electrode 110. When the first electrode 110 is an anode, a high work function material that may easily inject holes may be used as a material for a first electrode.

The first electrode 110 may be a reflective electrode, a semi-transmissive electrode, or a transmissive electrode. When the first electrode 110 is a transmissive electrode, a material for forming the first electrode 110 may be an indium tin oxide (ITO), an indium zinc oxide (IZO), a tin oxide (SnO₂), a zinc oxide (ZnO), or any combinations thereof, but the exemplary embodiments are not limited thereto. In some exemplary embodiments, when the first electrode 110 is a semi-transmissive electrode or a reflective electrode, magnesium (Mg), silver (Ag), aluminum (Al), aluminum-lithium (Al—Li), calcium (Ca), magnesium-indium (Mg—In), magnesium-silver (Mg—Ag), or any combination thereof may be used as a material for forming the first electrode 110, but the exemplary embodiments are not limited thereto.

The first electrode 110 may have a single-layered structure consisting of a single layer or a multi-layered structure including two or more layers. In some exemplary embodiments, the first electrode 110 may have a triple-layered structure of ITO/Ag/ITO, but the exemplary embodiments are not limited thereto.

Interlayer 150

The interlayer 150 may be on the first electrode 110. The interlayer 150 may include an emission layer. The interlayer 150 may further include a hole transport region between the first electrode 110 and the emission layer and an electron transport region between the emission layer and the second electrode 190. The interlayer 150 may further include metal-containing compounds such as organometallic compounds, inorganic materials such as quantum dots, and the like, in addition to various organic materials.

Hole Transport Region in Interlayer 150

The hole transport region may have i) a single-layered structure consisting of a single layer consisting of a single material, ii) a single-layered structure consisting of a single layer including a plurality of different materials, or iii) a multi-layered structure having a plurality of layers including a plurality of different materials.

The hole transport region may include a hole injection layer (HIL), a hole transport layer (HTL), an emission auxiliary layer, an electron blocking layer (EBL), or a combination thereof. For example, the hole transport region may have a multi-layered structure, e.g., a hole injection layer/hole transport layer structure, a hole injection layer/hole transport layer/emission auxiliary layer structure, a hole injection layer/emission auxiliary layer structure, a hole transport layer/emission auxiliary layer structure, or a hole injection layer/hole transport layer/electron blocking layer structure, wherein layers of each structure are sequentially stacked on the first electrode 110 in each stated order, but the exemplary embodiments are not limited thereto.

The hole transport region may include the compound represented by Formula 201, the compound represented by Formula 202, or any combination thereof:

-   -   wherein, in Formulae 201 and 202,     -   L201 to L204 may each independently be a substituted or         unsubstituted C3-C10 cycloalkylene group, a substituted or         unsubstituted C1-C10 heterocycloalkylene group, a substituted or         unsubstituted C3-C10 cycloalkenylene group, a substituted or         unsubstituted C1-C10 heterocycloalkenylene group, a substituted         or unsubstituted C6-C60 arylene group, a substituted or         unsubstituted C1-C60 heteroarylene group, a substituted or         unsubstituted divalent non-aromatic condensed polycyclic group,         or a substituted or unsubstituted divalent non-aromatic         condensed heteropolycyclic group,     -   L₂₀₅ may be *—O—*′, *—S—*′, *—N(Q₂₀₁)-*′, a substituted or         unsubstituted C₁-C₂₀ alkylene group, a substituted or         unsubstituted C₂-C₂₀ alkenylene group, a substituted or         unsubstituted C₃-C₁₀ cycloalkylene group, a substituted or         unsubstituted C₁-C₁₀ heterocycloalkylene group, a substituted or         unsubstituted C₃-C₁₀ cycloalkenylene group, a substituted or         unsubstituted C₁-C₁₀ heterocycloalkenylene group, a substituted         or unsubstituted C₆-C₆₀ arylene group, a substituted or         unsubstituted C₁-C₆₀ heteroarylene group, a substituted or         unsubstituted divalent non-aromatic condensed polycyclic group,         or a substituted or unsubstituted divalent non-aromatic         condensed heteropolycyclic group,     -   xa1 to xa4 may each independently be 0, 1, 2, or 3 (e.g., 0, 1,         or 2),     -   xa5 may be an integer from 1 to 10 (e.g., 1, 2, 3, or 4), and     -   R₂₀₁ to R₂₀₄ and Q₂₀₁ may each independently be a substituted or         unsubstituted C₃-C₁₀ cycloalkyl group, a substituted or         unsubstituted C₁-C₁₀ heterocycloalkyl group, a substituted or         unsubstituted C₃-C₁₀ cycloalkenyl group, a substituted or         unsubstituted C₁-C₁₀ heterocycloalkenyl group, a substituted or         unsubstituted C₆-C₆₀ aryl group, a substituted or unsubstituted         C₆-C₆₀ aryloxy group, a substituted or unsubstituted C₆-C₆₀         arylthio group, a substituted or unsubstituted C₁-C₆₀ heteroaryl         group, a substituted or unsubstituted monovalent non-aromatic         condensed polycyclic group, or a substituted or unsubstituted         monovalent non-aromatic condensed heteropolycyclic group.

In some exemplary embodiments, in Formula 202, R₂₀₁ and R₂₀₂ may optionally be bound via a single bond, a dimethyl-methylene group, or a diphenyl-methylene group, and R₂₀₃ and R₂₀₄ may optionally be bound via a single bond, a dimethyl-methylene group, or a diphenyl-methylene group.

In some exemplary embodiments, i) at least one of R₂₀₁ to R₂₀₃ in Formula 201 and ii) at least one of R₂₀₁ to R₂₀₄ in Formula 202 may each independently be a fluorenyl group, a spiro-bifluorenyl group, a benzofluorenyl group, an indenophenanthrenyl group, a pyridinyl group, a pyrrolyl group, a thiophenyl group, a furanyl group, an indolyl group, a benzoindolyl group, an isoindolyl group, a benzoisoindolyl group, a benzosilolyl group, a benzothiophenyl group, a benzofuranyl group, a carbazolyl group, a dibenzosilolyl group, a dibenzothiophenyl group, or a dibenzofuranyl group, each unsubstituted or substituted with at least one of deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, a C₁-C₂₀ alkyl group, a C₁-C₁₀ alkoxy group, a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, a cyclopentenyl group, a cyclohexenyl group, a phenyl group, a biphenyl group, a terphenyl group, a phenyl group substituted with a C₁-C₁₀ alkyl group, a phenyl group substituted with —F, a naphthyl group, a phenanthrenyl group, an indenyl group, a fluorenyl group, a dimethylfluorenyl group, a diphenylfluorenyl group, a spiro-bifluorenyl group, a benzofluorenyl group, a dimethyl benzofluorenyl group, a diphenylbenzofluorenyl group, an indenophenanthrenyl group, a dimethylindenophenanthrenyl group, a diphenylindenophenanthrenyl group, a pyridinyl group, a pyrrolyl group, a thiophenyl group, a furanyl group, an indolyl group, a phenylindolyl group, a benzoindolyl group, a phenylbenzoindolyl group, an isoindolyl group, a phenylisoindolyl group, a benzoisoindolyl group, a phenylbenzoisoindolyl group, a benzosilolyl group, a dimethylbenzosilolyl group, a diphenylbenzosilolyl group, a benzothiophenyl group, a benzofuranyl group, a carbazolyl group, a phenylcarbazolyl group, a biphenylcarbazolyl group, a dibenzosilolyl group, a dimethyl dibenzosilolyl group, a diphenyldibenzosilolyl group, a dibenzothiophenyl group, and a dibenzofuranyl group, but the exemplary embodiments are not limited thereto.

In some exemplary embodiments, the compound represented by Formula 201 or 202 may include at least one carbazole group. In some exemplary embodiments, the compound represented by Formula 201 may not include a carbazole group. In some exemplary embodiments, the compound represented by Formula 201 may be represented by Formula 201A-1:

-   -   wherein, in Formula 201A-1, L₂₀₃, xa3, and R₂₀₃ in Formula         201A-1 may respectively be understood by referring to the         descriptions of L₂₀₃, xa3, and R₂₀₃ provided herein, and R₂₁₁ to         R₁₂₆ may each independently be hydrogen, deuterium, —F, —Cl,         —Br, —I, a hydroxyl group, a cyano group, a nitro group, a         C₁-C₂₀ alkyl group, a C₁-C₂₀ alkoxy group, a cyclopentyl group,         a cyclohexyl group, a cycloheptyl group, a cyclopentenyl group,         a cyclohexenyl group, a phenyl group, a biphenyl group, a         terphenyl group, a phenyl group substituted with a C₁-C₁₀ alkyl         group, a phenyl group substituted with —F, a naphthyl group, a         phenanthrenyl group, an indenyl group, a fluorenyl group, a         dimethylfluorenyl group, a diphenylfluorenyl group, a         spiro-bifluorenyl group, a benzofluorenyl group, a         dimethylbenzofluorenyl group, a diphenylbenzofluorenyl group, an         indenophenanthrenyl group, a dimethylindenophenanthrenyl group,         a diphenylindenophenanthrenyl group, a pyridinyl group, a         pyrrolyl group, a thiophenyl group, a furanyl group, an indolyl         group, a phenylindolyl group, a benzoindolyl group, a         phenylbenzoindolyl group, an isoindolyl group, a         phenylisoindolyl group, a benzoisoindolyl group, a         phenylbenzoisoindolyl group, a benzosilolyl group, a         dimethylbenzosilolyl group, a diphenylbenzosilolyl group, a         benzothiophenyl group, a benzofuranyl group, a carbazolyl group,         a phenylcarbazolyl group, a biphenylcarbazolyl group, a         dibenzosilolyl group, a dimethyldibenzosilolyl group, a         diphenyldibenzosilolyl group, a dibenzothiophenyl group, or a         dibenzofuranyl group.

In some exemplary embodiments, the hole transport region may include one of Compounds HT1 to HT44 and 4,4′,4″-tris[phenyl(m-tolyl)amino]triphenylamine (m-MTDATA), 1-N, 1-N-bis[4-(diphenylamino)phenyl]-4-N,4-N-diphenylbenzene-1,4-diamine (TDATA), 4,4′,4″-tris[2-naphthyl(phenyl)amino]triphenylamine (2-TNATA), N,N′-di(1-naphthyl)-N,N′-diphenyl-(1,1′-biphenyl)-4,4′-diamine (NPB or NPD), N4,N4′-di(naphthalen-2-yl)-N4,N4′-diphenyl-[1,1′-biphenyl]-4,4′-diamine (β-NPB), N,N′-bis(3-methylphenyl)-N,N′-diphenylbenzidine (TPD), N,N′-bis(3-methylphenyl)-N,N′-diphenyl-9,9-spirobifluorene-2,7-diamine (spiro-TPD), N2,N7-di-1-naphthalenyl-N2,N7-diphenyl-9,9′-spirobi[9H-fluorene]-2,7-diamine (spiro-NPB), N, N,N′-di(1-naphthyl)-N,N′-2,2′dimethyldiphenyl-(1,1′-biphenyl)-4,4′-diamine (methylated-NPB), 4,4′-cyclohexylidenebis[N,N-bis(4-methylphenyl)benzenamine] (TAPC), N,N,N′,N′-tetrakis(3-methylphenyl)-3,3′-dimethylbenzidine (HMTPD), 4,4′,4″-tris(N-carbazolyl)triphenylamine (TCTA), polyaniline/dodecylbenzenesulfonic acid (PANI/DBSA), poly(3,4-ethylenedioxythiophene)/poly(4-styrenesulfonate) (PEDOT/PSS), polyaniline/camphorsulfonic acid (PANI/CSA), polyaniline/poly(4-styrenesulfonate (PANI/PSS), or any combination thereof, but the exemplary embodiments are not limited thereto:

The thickness of the hole transport region may be in a range of about 100 Angstroms (Å) to about 10,000 Å, for example, about 100 Å to about 1,000 Å. When the hole transport region includes at least one selected from the hole injection layer and the hole transport layer, the thickness of the hole injection layer may be in a range of about 100 Å to about 9,000 Å, for example, about 100 Å to about 1,000 Å, the thickness of the hole transport layer may be in a range of about 50 Å to about 2,000 Å, for example, about 100 Å to about 1,500 Å. When the thicknesses of the hole transport region, the hole injection layer, and the hole transport layer are within any of these ranges, excellent hole transport characteristics may be obtained without a substantial increase in driving voltage.

The emission auxiliary layer may increase light emission efficiency by compensating for an optical resonance distance according to the wavelength of light emitted by an emission layer. The electron blocking layer may reduce or eliminate the flow of electrons from an electron transport region. The emission auxiliary layer and the electron blocking layer may include the aforementioned materials.

p-Dopant

The hole transport region may include a charge generating material as well as the aforementioned materials to improve conductive properties of the hole transport region. The charge generating material may be substantially homogeneously or non-homogeneously dispersed in the hole transport region.

The charge generating material may include, for example, a p-dopant. In some exemplary embodiments, a LUMO energy level of the p-dopant may be about −3.5 eV or less. The p-dopant may be a quinone derivative, a metal oxide, a compound containing a cyano group, or any combination thereof, but the exemplary embodiments are not limited thereto.

In some exemplary embodiments, the p-dopant may include: a quinone derivative such as TCNQ or F4-TCNQ; a metal oxide, such as tungsten oxide or molybdenum oxide; a cyano group-containing compound such as HAT-CN; a compound represented by Formula 221, or any combination thereof, but the exemplary embodiments are not limited thereto.

-   -   wherein, in Formula 221,     -   R₂₂₁ to R₂₂₃ may each independently be a substituted or         unsubstituted C₃-C₁₀ cycloalkyl group, a substituted or         unsubstituted C₁-C₁₀ heterocycloalkyl group, a substituted or         unsubstituted C₃-C₁₀ cycloalkenyl group, a substituted or         unsubstituted C₁-C₁₀ heterocycloalkenyl group, a substituted or         unsubstituted C₆-C₆₀ aryl group, a substituted or unsubstituted         C₁-C₆₀ heteroaryl group, a substituted or unsubstituted         monovalent non-aromatic condensed polycyclic group, or a         substituted or unsubstituted monovalent non-aromatic condensed         heteropoly cyclic group, wherein at least one of R₂₂₁ to R₂₂₃         may each independently be a C₃-C₁₀ cycloalkyl group, a C₁-C₁₀         heterocycloalkyl group, a C₃-C₁₀ cycloalkenyl group, a C₁-C₁₀         heterocycloalkenyl group, a C₆-C₆₀ aryl group, a C₁-C₆₀         heteroaryl group, a monovalent non-aromatic condensed polycyclic         group, or a monovalent non-aromatic condensed heteropolycyclic         group, each substituted with a cyano group; —F; —Cl; —Br; —I; a         C₁-C₂₀ alkyl group substituted with at least one cyano group; a         C₁-C₂₀ alkyl group substituted with at least —F; a C₁-C₂₀ alkyl         group substituted with at least —Cl; a C₁-C₂₀ alkyl group         substituted with at least —Br; a C₁-C₂₀ alkyl group substituted         with at least —I; or any combination thereof.

Emission Layer in Interlayer 150

When the light-emitting device 10 is a full color light-emitting device, the emission layer may be patterned into a red emission layer, a green emission layer, and/or a blue emission layer, according to a sub-pixel. In one or more exemplary embodiments, the emission layer may have a stacked structure. The stacked structure may include two or more layers selected from the red emission layer, the green emission layer, and the blue emission layer. The two or more layers may be in direct contact with each other. In some exemplary embodiments, the two or more layers may be separated from each other. In one or more exemplary embodiments, the emission layer may include two or more materials. The two or more materials may include the red light-emitting material, the green light-emitting material, or the blue light-emitting material. The two or more materials may be mixed with each other in a single layer. The two or more materials mixed with each other in the single layer may emit white light.

The emission layer may include a host and a dopant. The dopant may be a phosphorescent dopant, a fluorescent dopant, or any combination thereof. The amount of the dopant in the emission layer may be in a range of about 0.01 parts to about 15 parts by weight based on 100 parts by weight of the host, but the exemplary embodiments are not limited thereto. In some exemplary embodiments, the emission layer may include a quantum dot. The thickness of the emission layer may be in a range of about 100 Å to about 1,000 Å, and in some exemplary embodiments, about 200 Å to about 600 Å. When the thickness of the emission layer is within any of these ranges, improved luminescence characteristics may be obtained without a substantial increase in driving voltage.

Host in Emission Layer

The host may include a compound represented by Formula 301: [Ar₃₀₁]_(xb11)-[(L₃₀₁)_(xb1)-R₃₀₁]_(xb21)  Formula 301

-   -   wherein, in Formula 301,     -   Ar₃₀₁ may be selected from a substituted or unsubstituted C₁-C₆₀         carbocyclic group and a substituted or unsubstituted C₁-C₆₀         heterocyclic group,     -   xb11 may be 1, 2, or 3,     -   L₃₀₁ may be a substituted or unsubstituted C₃-C₁₀ cycloalkylene         group, a substituted or unsubstituted C₁-C₁₀ heterocycloalkylene         group, a substituted or unsubstituted C₃-C₁₀ cycloalkenylene         group, a substituted or unsubstituted C₁-C₁₀         heterocycloalkenylene group, a substituted or unsubstituted         C₆-C₆₀ arylene group, a substituted or unsubstituted C₁-C₆₀         heteroarylene group, a substituted or unsubstituted divalent         non-aromatic condensed polycyclic group, or a substituted or         unsubstituted divalent non-aromatic condensed heteropolycyclic         group,     -   xb1 may be 0, 1, 2, 3, 4, or 5,     -   R₃₀₁ may be deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a         cyano group, a nitro group, a substituted or unsubstituted         C₁-C₆₀ alkyl group, a substituted or unsubstituted C₂-C₆₀         alkenyl group, a substituted or unsubstituted C₂-Go alkynyl         group, a substituted or unsubstituted C₁-C₆₀ alkoxy group, a         substituted or unsubstituted C₃-C₁₀ cycloalkyl group, a         substituted or unsubstituted C₁-C₁₀ heterocycloalkyl group, a         substituted or unsubstituted C₃-C₁₀ cycloalkenyl group, a         substituted or unsubstituted C₁-C₁₀ heterocycloalkenyl group, a         substituted or unsubstituted C₆-C₆₀ aryl group, a substituted or         unsubstituted C₆-C₆₀ aryloxy group, a substituted or         unsubstituted C₆-C₆₀ arylthio group, a substituted or         unsubstituted C₁-C₆₀ heteroaryl group, a substituted or         unsubstituted monovalent non-aromatic condensed polycyclic         group, a substituted or unsubstituted monovalent non-aromatic         condensed heteropolycyclic group, —Si(Q₃₀₁)(Q₃₀₂)(Q₃₀₃),         —N(Q₃₀₁)(Q₃₀₂), —B(Q₃₀₁)(Q₃₀₂), —C(═O)(Q₃₀₁), —S(═O)₂(Q₃₀₁), or         —P(═O)(Q₃₀₁)(Q₃₀₂),     -   xb21 may be 1, 2, 3, 4, or 5, and     -   Q₃₀₁ to Q₃₀₃ may each be understood by referring to the         descriptions of Q₁ provided herein.

In some exemplary embodiments, when xb11 in Formula 301 is 2 or greater, at least two Ar₃₀₁(s) may be bound via a single bond. In some exemplary embodiments, the host may include a compound represented by Formula 301-1, a compound represented by Formula 301-2, or any combination thereof:

-   -   wherein, in Formulae 301-1 to 301-2,     -   ring A₃₀₁ to ring A₃₀₄ may each independently be a C₅-C₆₀         carbocyclic group or a C₁-C₆₀ heterocyclic group,     -   X₃₀₁ may be O, S, N-[(L₃₀₄)_(xb4)-R₃₀₄], C(R₃₀₄)(R₃₀₅), or         Si(R₃₀₄)(R₃₀₅),     -   xb22 and xb23 may each independently be 0, 1, or 2,     -   L₃₀₁, xb1, and R₃₀₁ may respectively be understood by referring         to the descriptions of L₃₀₁, xb1, and R₃₀₁ provided herein,     -   L₃₀₂ to L₃₀₄ may each be understood by referring to the         descriptions of L₃₀₁ provided herein,     -   xb2 to xb4 may each be understood by referring to the         descriptions of xb1 provided herein, and     -   R₃₀₂ to R₃₀₅ and R₃₁₁ to R₃₁₄ may each be understood by         referring to the descriptions of R₃₀₁ provided herein.

In some exemplary embodiments, the host may include an alkaline earth metal complex. For example, the host may include a Be complex (e.g., Compound H55), a Mg complex, a Zn complex, or any combination thereof. In some exemplary embodiments, the host may include one of Compounds H1 to H120, 9,10-di(2-naphthyl)anthracene (ADN), 2-methyl-9,10-bis(naphthalen-2-yl)anthracene (MADN), 9,10-di-(2-naphthyl)-2-t-butyl-anthracene (TBADN), 4,4′-bis(N-carbazolyl)-1,1′-biphenyl (CBP), 1,3-di-9-carbazolylbenzene (mCP), 1,3,5-tri(carbazol-9-yl)benzene (TCP), or any combination thereof, but the exemplary embodiments are not limited thereto:

Phosphorescent Dopant Included in Emission Layer of Interlayer 150

The phosphorescent dopant may include at least one transition metal as a center metal. The phosphorescent dopant may include a monodentate ligand, a bidentate ligand, a tridentate ligand, a tetradentate ligand, a pentadentate ligand, a hexadentate ligand, or any combination thereof. The phosphorescent dopant may be electrically neutral.

In some exemplary embodiments, the phosphorescent dopant may include an organometallic complex represented by Formula 401:

-   -   wherein, in Formulae 401 and 402,     -   M may be transition metal (e.g., iridium (Ir), platinum (Pt),         palladium (Pd), osmium (Os), titanium (Ti), gold (Au), hafnium         (Hf), europium (Eu), terbium (Tb), rhodium (Rh), rhenium (Re),         or thulium (Tm)),     -   L₄₀₁ may be a ligand represented by Formula 402, and xc1 may be         1, 2, or 3, and when xc1 is 2 or greater, at least two L₄₀₁(s)         may be identical to or different from each other,     -   L₄₀₂ may be an organic ligand, and xc2 may be an integer from 0         to 4, and when xc2 is 2 or greater, at least two L₄₀₂(s) may be         identical to or different from each other,     -   X₄₀₁ and X₄₀₂ may each independently be a nitrogen or a carbon,     -   ring A₄₀₁ and ring A₄₀₂ may each independently be a C₅-C₆₀         carbocyclic group or a C₁-C₆₀ heterocyclic group,     -   T₄₀₁ may be a single bond, *—O—*′, *—S—*′, *—C(═O)—*′,         *—N(Q₄₁₁)-*′, *—C(Q₄₁₁)(Q₄₁₂)-*′, *—C(Q₄₁₁)=C(Q₄₁₂)-*′,         *—C(Q₄₁₁)=*′, or *═C(Q₄₁₁)=*′,     -   X₄₀₃ and X₄₀₄ may each independently be a chemical bond (e.g., a         covalent bond or a coordinate bond), O, S, N(Q₄₁₃), B(Q₄₁₃),         P(Q₄₁₃), C(Q₄₁₃)(Q₄₁₄), or Si(Q₄₁₃)(Q₄₁₄),     -   Q₄₁₁ to Q₄₁₄ may each be understood by referring to the         descriptions of Q₁ provided herein,     -   R₄₀₁ and R₄₀₂ may each independently be hydrogen, deuterium, —F,         —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, a         substituted or unsubstituted C₁-C₂₀ alkyl group, a substituted         or unsubstituted C₁-C₂₀ alkoxy group, a substituted or         unsubstituted C₃-C₁₀ cycloalkyl group, a substituted or         unsubstituted C₁-C₁₀ heterocycloalkyl group, a substituted or         unsubstituted C₃-C₁₀ cycloalkenyl group, a substituted or         unsubstituted C₁-C₁₀ heterocycloalkenyl group, a substituted or         unsubstituted C₆-C₆₀ aryl group, a substituted or unsubstituted         C₆-C₆₀ aryloxy group, a substituted or unsubstituted C₆-C₆₀         arylthio group, a substituted or unsubstituted C₁-C₆₀ heteroaryl         group, a substituted or unsubstituted monovalent non-aromatic         condensed polycyclic group and a substituted or unsubstituted         monovalent non-aromatic condensed heteropolycyclic group,         —Si(Q₄₀₁)(Q₄₀₂)(Q₄₀₃), —N(Q₄₀₁)(Q₄₀₂), —B(Q₄₀₁)(Q₄₀₂),         —C(═O)(Q₄₀₁), —S(═O)₂(Q₄₀₁), or —P(═O)(Q₄₀₁)(Q₄₀₂),     -   Q₄₀₁ to Q₄₀₃ may each be understood by referring to the         description of Q₁ provided herein,     -   xc11 and xc12 may each independently be an integer from 0 to 10,         and     -   and *′ in Formula 402 each indicate a binding site to M in         Formula 401.

In one or more exemplary embodiments, in Formula 402, i) X₄₀₁ may be nitrogen, and X₄₀₂ may be carbon, or ii) X₄₀₁ and X₄₀₂ may both be nitrogen.

In one or more exemplary embodiments, when xc1 in Formula 402 is 2 or greater, two ring A₄₀₁(s) of at least two L₄₀₁(s) may optionally be bound via T₄₀₂ as a linking group, or two ring A₄₀₂(s) may optionally be bound via T₄₀₃ as a linking group (see Compounds PD1 to PD4 and PD7). T₄₀₂ and T₄₀₃ may each be understood by referring to the description of T₄₀₁ provided herein.

-   -   L₄₀₂ in Formula 401 may be any suitable organic ligand. For         example, L₄₀₂ may be a halogen group, a diketone group (e.g., an         acetylacetonate group), a carboxylic acid group (e.g., a         picolinate group), —C(═O), an isonitrile group, —CN, or a         phosphorus group (e.g., a phosphine group or a phosphite group),         but the exemplary embodiments are not limited thereto.

The phosphorescent dopant may be, for example, one of Compounds PD1 to PD25 or any combination thereof, but the exemplary embodiments are not limited thereto:

Fluorescent Dopant in Emission Layer

The fluorescent dopant may include a compound represented by Formula 1.

The fluorescent dopant may further include, in addition to the compound of Formula 1, an amine group-containing compound, a styryl group-containing compound, or any combination thereof.

In some exemplary embodiments, the fluorescent dopant may include a compound represented by Formula 501:

-   -   wherein, in Formula 501,     -   Ar₅₀₁ may be selected from a substituted or unsubstituted C₅-C₆₀         carbocyclic group and a substituted or unsubstituted C₁-C₆₀         heterocyclic group,     -   L₅₀₁ to L₅₀₃ may each independently be a substituted or         unsubstituted C₃-C₁₀ cycloalkylene group, a substituted or         unsubstituted C₁-C₁₀ heterocycloalkylene group, a substituted or         unsubstituted C₃-C₁₀ cycloalkenylene group, a substituted or         unsubstituted C₁-C₁₀ heterocycloalkenylene group, a substituted         or unsubstituted C₆-C₆₀ arylene group, a substituted or         unsubstituted C₁-C₆₀ heteroarylene group, a substituted or         unsubstituted divalent non-aromatic condensed polycyclic group,         or a substituted or unsubstituted divalent non-aromatic         condensed heteropolycyclic group,     -   xd1 to xd3 may each independently be 0, 1, 2, or 3,     -   R₅₀₁ and R₅₀₂ may each independently be a substituted or         unsubstituted C₃-C₁₀ cycloalkyl group, a substituted or         unsubstituted C₁-C₁₀ heterocycloalkyl group, a substituted or         unsubstituted C₃-C₁₀ cycloalkenyl group, a substituted or         unsubstituted C₁-C₁₀ heterocycloalkenyl group, a substituted or         unsubstituted C₆-C₆₀ aryl group, a substituted or unsubstituted         C₆-C₆₀ aryloxy group, a substituted or unsubstituted C₆-C₆₀         arylthio group, a substituted or unsubstituted C₁-C₆₀ heteroaryl         group, a substituted or unsubstituted monovalent non-aromatic         condensed polycyclic group, or a substituted or unsubstituted         monovalent non-aromatic condensed heteropolycyclic group, and     -   xd4 may be 1, 2, 3, 4, 5, or 6.

In some exemplary embodiments, in Formula 501, Ar₅₀₁ may be a condensed ring (e.g., an anthracene group, a chrysene group, or a pyrene group) in which at least three monocyclic groups are condensed. In some exemplary embodiments, xd4 in Formula 501 may be 2, but the exemplary embodiments are not limited thereto.

In some exemplary embodiments, the fluorescent dopant may include one of Compounds FD1 to FD36, DPVBi, DPAVBi, or any combination thereof:

Quantum Dot in Emission Layer

The emission layer may include a quantum dot. Quantum dots arranged in the quantum dot emission layer may be synthesized by a wet chemical process, an organic metal chemical vapor deposition process, a molecular beam epitaxy process, or any similar process.

The wet chemical process is a method of growing a quantum dot particle crystal by adding a precursor material in an organic solvent. When the crystal grows, the organic solvent may naturally serve as a dispersant coordinated on the surface of the quantum dot crystal and control the growth of the crystal. Thus, the wet chemical method may be easier than the vapor deposition process such as the metal organic chemical vapor deposition (MOCVD) or the molecular beam epitaxy (MBE) process. Further, the growth of quantum dot particles may be controlled with a lower manufacturing cost. In some exemplary embodiments, the quantum dot may be a III-VI group semiconductor compound; a II-VI group semiconductor compound; a III-V group semiconductor compound; a IV-VI group semiconductor compound; a IV group element or compound; or any combination thereof.

In some exemplary embodiments, the III-VI group semiconductor compound may be a binary compound such as In₂S₃; a tertiary compound such as AgInS, AgInS₂, CuInS, or CuInS₂; or any combination thereof. In some exemplary embodiments, the II-VI group semiconductor compound may include a binary compound such as CdSe, CdTe, ZnS, ZnSe, ZnTe, ZnO, HgS, HgSe, HgTe, MgSe, orMgS; a ternary compound such as CdSeS, CdSeTe, CdSTe, ZnSeS, ZnSeTe, ZnSTe, HgSeS, HgSeTe, HgSTe, CdZnS, CdZnSe, CdZnTe, CdHgS, CdHgSe, CdHgTe, HgZnS, HgZnSe, HgZnTe, MgZnSe, orMgZnS; a quaternary compound such as CdZnSeS, CdZnSeTe, CdZnSTe, CdHgSeS, CdHgSeTe, CdHgSTe, HgZnSeS, HgZnSeTe, or HgZnSTe; or any combination thereof.

In some exemplary embodiments, the III-V group semiconductor compound may be a binary compound such as GaN, GaP, GaAs, GaSb, AlN, AlP, AlAs, AlSb, InN, InP, InAs, or InSb; a ternary compound such as GaNP, GaNAs, GaNSb, GaPAs, GaPSb, AlNP, AlNAs, AlNSb, AlPAs, AlPSb, InGaP, InNP, InNAs, InNSb, InPAs, or InPSb; a quaternary compound such as GaAlNAs, GaAlNSb, GaAlPAs, GaAlNP, GaAlPSb, GaInNP, GaInNAs, GaInNSb, GaInPAs, GaInPSb, InAlNP, InAlNAs, InAlNSb, InAlPAs, or InAlPSb; or any combination thereof. In some exemplary embodiments, the IV-VI group semiconductor compound may be a binary compound such as SnS, SnSe, SnTe, PbS, PbSe, or PbTe; a ternary compound such as SnSeS, SnSeTe, SnSTe, PbSeS, PbSeTe, PbSTe, SnPbS, SnPbSe, or SnPbTe; a quaternary compound such as SnPbSSe, SnPbSeTe, or SnPbSTe; or any combination thereof.

In some exemplary embodiments, the IV group element or compound may be a single element compound such as Si or Ge; a binary compound such as SiC or SiGe; or any combination thereof. In this case, each element included in the binary compound, the ternary compound, or the quaternary compound may be present in particles at a uniform concentration or in the same particle by being partially divided into different concentrations.

The quantum dot may have a single structure in which the concentration of each element included in the quantum dot is uniform or a core-shell double structure. In some exemplary embodiments, materials included in the core may be different from materials included in the shell. The shell of the quantum dot may serve as a protective layer for preventing chemical denaturation of the core to maintain semiconductor characteristics and/or as a charging layer for imparting electrophoretic characteristics to the quantum dot. The shell may be monolayer or multilayer. An interface between a core and a shell may have a concentration gradient where a concentration of elements present in the shell decreases toward the center.

Examples of the shell of the quantum dot include metal or nonmetal oxide, a semiconductor compound, or a combination thereof. In some exemplary embodiments, the metal or nonmetal oxide may include a binary compound such as SiO₂, Al₂O₃, TiO₂, ZnO, MnO, Mn₂O₃, Mn₃O₄, CuO, FeO, Fe₂O₃, Fe₃O₄, CoO, Co₃O₄, or NiO or a ternary compound such as MgAl₂O₄, CoFe₂O₄, NiFe₂O₄, or CoMn₂O₄, but the exemplary embodiments are not limited thereto. In some exemplary embodiments, the semiconductor compound may be CdS, CdSe, CdTe, ZnS, ZnSe, ZnTe, ZnSeS, ZnTeS, GaAs, GaP, GaSb, HgS, HgSe, HgTe, InAs, InP, InGaP, InSb, AlAs, AlP, or AlSb, but the exemplary embodiments are not limited thereto.

The quantum dot may have the full width of half maximum (FWHM) of a spectrum of the emission wavelength of about 45 nm or less, about 40 nm or less, or about 30 nm or less. When the FWHM of the quantum dot is within this range, color purity or color reproducibility may be improved. In addition, since light emitted through the quantum dot is emitted in all directions, an optical viewing angle may be improved.

In addition, the quantum dot may be specifically, a generally spherical form, a generally pyramidal form, a generally multi-armed form, or a generally cubic nanoparticle, a generally shaped nanotube, a generally shaped nanowire, a generally shaped nanofiber, or a generally shaped nanoplate particle, but the exemplary embodiments are not limited thereto.

By adjusting the size of the quantum dot, the energy band gap may also be adjusted, thereby obtaining light of various wavelengths in the quantum dot emission layer. By using quantum dots of various sizes, a light-emitting device that may emit light of various wavelengths may be realized. In some exemplary embodiments, the size of the quantum dot may be selected such that the quantum dot may emit red, green, and/or blue light. In addition, the size of the quantum dot may be selected such that the quantum dot may emit white light by combining various light of colors.

Electron Transport Region in Interlayer 150

The electron transport region may have i) a single-layered structure consisting of a single layer consisting of a single material, ii) a single-layered structure consisting of a single layer including a plurality of different materials, or iii) a multi-layered structure having a plurality of layers including a plurality of different materials.

The electron transport region may include a buffer layer, a hole blocking layer, an electron control layer, an electron transport layer, or an electron injection layer, but the exemplary embodiments are not limited thereto.

In some exemplary embodiments, the electron transport region may have an electron transport layer/electron injection layer structure, a hole blocking layer/electron transport layer/electron injection layer structure, an electron control layer/electron transport layer/electron injection layer structure, or a buffer layer/electron transport layer/electron injection layer structure, wherein layers of each structure are sequentially stacked on the emission layer in each stated order, but the exemplary embodiments are not limited thereto.

The electron transport region (for example, the buffer layer, the hole blocking layer, the electron control layer, or the electron transport layer in the electron transport region) may include a metal-free compound including at least one π electron deficient nitrogen-containing cyclic group that may easily accept electrons.

For example, the “π electron deficient nitrogen-containing cyclic group” may be i) a first ring, ii) a condensed cyclic group in which two or more first rings are condensed, or iii) a condensed cyclic group in which at least one first ring and at least one second ring are condensed, wherein the first ring is a heteromonocyclic group (for example, an imidazole group, a pyridine group, or a triazine group) which includes at least one *—N═*′ moiety as a ring-forming moiety, and the second ring is a cyclic group (for example, a benzene group, a dibenzofuran group, or a carbazole group) which does not include *—N═*′ moiety as a ring-forming moiety.

Examples of the π electron deficient nitrogen-containing cyclic group include a pyridine group, a pyrimidine group, a pyrazine group, a pyridazine group, a triazine group, a quinoline group, a benzoquinoline group, an isoquinoline group, a benzoisoquinoline group, a quinoxaline group, a benzoquinoxaline group, a quinazoline group, a benzoquinazoline group, a cinnoline group, a phenanthroline group, a phthalazine group, a naphthyridine group, an azacarbazole group, an azafluorene group, an azadibenzosilole group, an azadibenzothiophene group, an azadibenzofuran group, a pyrazole group, an imidazole group, a triazole group, a tetrazole group, an oxazole group, an isooxazole group, a thiazole group, an isothiazole group, an oxadiazole group, a thiadiazole group, a benzopyrazole group, a benzimidazole group, a benzoxazole group, a benzothiazole group, a benzoxadiazole group, a benzothiadiazole group, an imidazopyridine group, an imidazopyrimidine group, an imidazotriazine group, an imidazopyrazine group, and an imidazopyridazine group, but the exemplary embodiments are not limited thereto.

For example, the electron transport region may include a compound represented by Formula 601 and including at least one π electron deficient nitrogen-containing cyclic group. [Ar₆₀₁]_(xe11)-[(L₆₀₁)_(xe11)-R₆₀₁]_(xe21)  Formula 601

-   -   wherein, in Formula 601,     -   Ar₆₀₁ may be selected from a substituted or unsubstituted C₅-C₆₀         carbocyclic group and a substituted or unsubstituted C₁-C₆₀         heterocyclic group,     -   xe11 may be 1, 2, or 3,     -   L₆₀₁ may be a substituted or unsubstituted C₃-C₁₀ cycloalkylene         group, a substituted or unsubstituted C₁-C₁₀ heterocycloalkylene         group, a substituted or unsubstituted C₃-C₁₀ cycloalkenylene         group, a substituted or unsubstituted C₁-C₁₀         heterocycloalkenylene group, a substituted or unsubstituted         C₆-C₆₀ arylene group, a substituted or unsubstituted C₁-C₆₀         heteroarylene group, a substituted or unsubstituted divalent         non-aromatic condensed polycyclic group, or a substituted or         unsubstituted divalent non-aromatic condensed heteropolycyclic         group,     -   xe1 may be 0, 1, 2, 3, 4, or 5,     -   R₆₀₁ may be a substituted or unsubstituted C₃-C₁₀ cycloalkyl         group, a substituted or unsubstituted C₁-C₁₀ heterocycloalkyl         group, a substituted or unsubstituted C₃-C₁₀ cycloalkenyl group,         a substituted or unsubstituted C₁-C₁₀ heterocycloalkenyl group,         a substituted or unsubstituted C₆-C₆₀ aryl group, a substituted         or unsubstituted C₆-C₆₀ aryloxy group, a substituted or         unsubstituted C₆-C₆₀ arylthio group, a substituted or         unsubstituted C₁-C₆₀ heteroaryl group, a substituted or         unsubstituted monovalent non-aromatic condensed polycyclic         group, a substituted or unsubstituted monovalent non-aromatic         condensed heteropolycyclic group, —Si(Q₆₀₁)(Q₆₀₂)(Q₆₀₃),         —C(═O)(Q₆₀₁), —S(═O)₂(Q₆OI), or —P(═O)(Q₆₀₁)(Q₆₀₂),     -   Q₆₀₁ to Q₆₀₃ may each be understood by referring to the         description of Q₁ provided herein, and     -   xe21 may be 1, 2, 3, 4, or 5.

In some exemplary embodiments, at least one of Ar₆₀₁, L₆₀₁, and R₆₀₁ in Formula 601 may each independently include the π-electron-depleted nitrogen-containing ring.

In some exemplary embodiments, when xe11 in Formula 601 is 2 or greater, at least two Ar₆₀₁(s) may be bound via a single bond.

In some exemplary embodiments, in Formula 601, Ar₆₀₁ may be a substituted or unsubstituted anthracene group.

In some exemplary embodiments, the electron transport region may include a compound represented by Formula 601-1:

-   -   wherein, in Formula 601-1,     -   X₆₁₄ may be N or C(R₆₁₄), X₆₁₅ may be N or C(R₆₁₅), X₆₁₆ may be         N or C(R₆₁₆), at least one selected from X₆₁₄ to X₆₁₆ may be N,     -   L₆₁₁ to L₆₁₃ may each be understood by referring to the         description of L₆₀₁ provided herein,     -   xe611 to xe613 may each be understood by referring to the         description of xe1 provided herein,     -   R₆₁₁ to R₆₁₃ may each be understood by referring to the         description of R₆₀₁ provided herein,     -   R₆₁₄ to R₆₁₆ may each independently be hydrogen, deuterium, —F,         —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, a         C₁-C₁₀ alkyl group, a C₁-C₂₀ alkoxy group, a phenyl group, a         biphenyl group, a terphenyl group, or a naphthyl group.

In some exemplary embodiments, in Formulae 601 and 601-1, xe1 and xe611 to xe613 may each independently be 0, 1, or 2.

The electron transport region may include one of Compounds ET1 to ET36, 2,9-dimethyl-4,7-diphenyl-1,10-phenanthroline (BCP), 4,7-diphenyl-1,10-phenanthroline (Bphen), tris-(8-hydroxyquinoline)aluminum (Alq₃), bis(2-methyl-8-quinolinolato-N1,O8)-(1,1′-biphenyl-4-olato)aluminum (BAlq), 3-(biphenyl-4-yl)-5-(4-tert-butylphenyl)-4-phenyl-4H-1,2,4-triazole (TAZ), 4-(naphthalen-1-yl)-3,5-diphenyl-4H-1,2,4-triazole (NTAZ), or any combination thereof, but the exemplary embodiments are not limited thereto:

The thicknesses of the buffer layer, the hole blocking layer, or the electron control layer may each independently be in a range of about 20 Å to about 1,000 Å, and in some exemplary embodiments, about 30 Å to about 300 Å. When the thicknesses of the buffer layer, the hole blocking layer or the electron control layer are within any of these ranges, excellent hole blocking characteristics or excellent electron controlling characteristics may be obtained without a substantial increase in driving voltage.

The thickness of the electron transport layer may be in a range of about 100 Å to about 1,000 Å, and in some exemplary embodiments, about 150 Å to about 500 Å. When the thickness of the electron transport layer is within any of these ranges, excellent electron transport characteristics may be obtained without a substantial increase in driving voltage.

The electron transport region (for example, the electron transport layer in the electron transport region) may further include, in addition to the materials described above, a metal-containing material.

The metal-containing material may include an alkali metal complex, an alkaline earth metal complex, or any combination thereof. A metal ion of the alkali metal complex may be a lithium (Li) ion, a sodium (Na) ion, a potassium (K) ion, a rubidium (Rb) ion, or a cesium (Cs) ion. A metal ion of the alkaline earth metal complex may be a beryllium (Be) ion, a magnesium (Mg) ion, a calcium (Ca) ion, a strontium (Sr) ion, or a barium (Ba) ion. Each ligand coordinated with the metal ion of the alkali metal complex and the alkaline earth metal complex may independently be hydroxyquinoline, hydroxyisoquinoline, hydroxybenzoquinoline, hydroxyacridine, hydroxyphenanthridine, hydroxyphenyloxazole, hydroxyphenylthiazole, hydroxyphenyloxadiazole, hydroxyphenylthiadiazole, hydroxyphenylpyridine, hydroxyphenylbenzimidazole, hydroxyphenylbenzothiazole, bipyridine, phenanthroline, cyclopentadiene, or any combination thereof, but the exemplary embodiments are not limited thereto.

For example, the metal-containing material may include a Li complex. The Li complex may include, e.g., Compound ET-D1 (lithium quinolate (LiQ)) or Compound ET-D2:

The electron transport region may include an electron injection layer that facilitates injection of electrons from the second electrode 190. The electron injection layer may be in direct contact with the second electrode 190.

The electron injection layer may have i) a single-layered structure consisting of a single layer consisting of a single material, ii) a single-layered structure consisting of a single layer including a plurality of different materials, or iii) a multi-layered structure having a plurality of layers including a plurality of different materials.

The electron injection layer may include an alkali metal, an alkaline earth metal, a rare earth metal, an alkali metal-containing compound, an alkaline earth metal-containing compound, a rare earth metal-containing compound, an alkali metal complex, an alkaline earth metal complex, a rare earth metal complex, or any combination thereof.

The alkali metal may be Li, Na, K, Rb, Cs or any combination thereof. The alkaline earth metal may be Mg, Ca, Sr, Ba, or any combination thereof. The rare earth metal may be Sc, Y, Ce, Tb, Yb, Gd, or any combination thereof.

The alkali metal-containing compound, the alkaline earth metal-containing compound, and the rare earth metal-containing compound may respectively be oxides, halides (e.g., fluorides, chlorides, bromides, or iodines), or any combination thereof of each of the alkali metal, the alkaline earth metal, and the rare earth metal.

The alkali metal-containing compound may be alkali metal oxides such as Li₂O, Cs₂O, or K₂O, alkali metal halides such as LiF, NaF, CsF, KF, LiI, NaI, CsI, or KI, or any combination thereof. The alkaline earth-metal-containing compound may include alkaline earth-metal compounds, such as BaO, SrO, CaO, Ba_(x)Sr_(1-x)O (wherein 0<x<1), or Ba_(x)Ca_(1-x)O (wherein 0<x<1). The rare earth metal-containing compound may include YbF₃, ScF₃, ScO₃, Y₂O₃, Ce₂O₃, GdF₃, TbF₃, YbI₃, ScI₃, TbI₃, or any combination thereof.

The alkali metal complex, the alkaline earth metal complex, and the rare earth metal complex may include: i) one of ions of the alkali metal, alkaline earth metal, and rare earth metal described above and ii) a ligand bound to the metal ion, e.g., hydroxyquinoline, hydroxyisoquinoline, hydroxybenzoquinoline, hydroxyacridine, hydroxyphenanthridine, hydroxyphenyloxazole, hydroxyphenylthiazole, hydroxydiaphenyloxadiazole, hydroxydiphenylthiadiazole, hydroxyphenylpyridine, hydroxyphenylbenzimidazole, hydroxyphenylbenzothiazole, bipyridine, phenanthroline, cyclopentadiene, or any combination thereof, but the exemplary embodiments are not limited thereto.

The electron injection layer may consist of an alkali metal, an alkaline earth metal, a rare earth metal, an alkali metal-containing compound, an alkaline earth metal-containing compound, a rare earth metal-containing compound, an alkali metal complex, an alkaline earth metal complex, a rare earth metal complex, or any combination thereof, as described above. In some exemplary embodiments, the electron injection layer may further include an organic material (e.g., a compound represented by Formula 601). When the electron injection layer further includes an organic material, the alkali metal, the alkaline earth metal, the rare earth metal, the alkali metal-containing compound, the alkaline earth metal-containing compound, the rare earth metal-containing compound, the alkali metal complex, the alkaline earth metal complex, the rare earth metal complex, or any combination thereof may be homogeneously or non-homogeneously dispersed in a matrix including the organic material.

The thickness of the electron injection layer may be in a range of about 1 Å to about 100 Å, and in some exemplary embodiments, about 3 Å to about 90 Å. When the thickness of the electron injection layer is within any of these ranges, excellent electron injection characteristics may be obtained without a substantial increase in driving voltage.

Second Electrode 190

The second electrode 190 may be on the interlayer 150. In an exemplary embodiment, the second electrode 190 may be a cathode that is an electron injection electrode. In this exemplary embodiment, a material for forming the second electrode 190 may be a material having a low work function, for example, a metal, an alloy, an electrically conductive compound, or any combination thereof.

The second electrode 190 may include lithium (Li), silver (Ag), magnesium (Mg), aluminum (Al), aluminum-lithium (Al—Li), calcium (Ca), magnesium-indium (Mg—In), magnesium-silver (Mg—Ag), an ITO, an IZO, or any combination thereof, but the exemplary embodiments are not limited thereto. The second electrode 190 may be a transmissive electrode, a semi-transmissive electrode, or a reflective electrode. The second electrode 190 may have a single-layered structure, or a multi-layered structure including two or more layers.

Capping Layer

A first capping layer may be located outside the first electrode 110, and/or a second capping layer may be located outside the second electrode 190. In some exemplary embodiments, the light-emitting device 10 may have a structure in which the first capping layer, the first electrode 110, the interlayer 150, and the second electrode 190 are sequentially stacked in this stated order, a structure in which the first electrode 110, the interlayer 150, the second electrode 190, and the second capping layer are sequentially stacked in this stated order, or a structure in which the first capping layer, the first electrode 110, the interlayer 150, the second electrode 190, and the second capping layer are sequentially stacked in this stated order.

A refractive index of the capping layer may be about 1.6 or higher. In some exemplary embodiments, a refractive index of the capping layer may be in a range of about 1.6 to about 2.0, about 1.6 to about 1.8, or about 1.7 to about 1.9. In the light-emitting device 10, light emitted from the emission layer in the interlayer 150 may pass through the first electrode 110 (which may be a semi-transmissive electrode or a transmissive electrode) and through the first capping layer to the outside. In the light-emitting device 10, light emitted from the emission layer in the interlayer 150 may pass through the second electrode 190 (which may be a semi-transmissive electrode or a transmissive electrode) and through the second capping layer to the outside.

The first capping layer and the second capping layer may improve the external luminescence efficiency based on the principle of constructive interference. The first capping layer and the second capping layer may each independently be a capping layer including an organic material, an inorganic capping layer including an inorganic material, or a composite capping layer including an organic material and an inorganic material.

At least one of the first capping layer and the second capping layer may each independently include carbocyclic compounds, heterocyclic compounds, amine group-containing compounds, porphine derivatives, phthalocyanine derivatives, naphthalocyanine derivatives, alkali metal complexes, alkaline earth metal complexes, or any combination thereof. The carbocyclic compound, the heterocyclic compound, and the amine group-containing compound may optionally be substituted with a substituent of O, N, S, Se, Si, F, Cl, Br, I, or any combination thereof. In some exemplary embodiments, at least one of the first capping layer and the second capping layer may each independently include an amine group-containing compound.

In some exemplary embodiments, at least one of the first capping layer and the second capping layer may each independently include the compound represented by Formula 201, the compound represented by Formula 202, or any combination thereof.

In one or more exemplary embodiments, at least one of the first capping layer and the second capping layer may each independently include a compound selected from Compounds HT28 to HT33, a compound selected Compounds CP1 to CP5, or any combination thereof, but the exemplary embodiments are not limited thereto:

Apparatus

The light-emitting device may be included in various apparatuses. In some exemplary embodiments, an emission apparatus, an authentication apparatus, or an electronic apparatus, each including the light-emitting device, may be provided.

The light-emitting device may further include a color filter in addition to the light-emitting device. The color filter may be disposed on at least one traveling direction of light emitted from the light-emitting device. In some exemplary embodiments, light emitted from the light-emitting device may be blue light, but the exemplary embodiments are not limited thereto. The light-emitting device may be understood by referring to the descriptions provided herein.

The emission apparatus may include a first substrate. The first substrate may include a plurality of sub-pixel areas, and the color filter may include a plurality of color filter areas respectively corresponding to the plurality of sub-pixel areas.

A pixel defining membrane may be located between the plurality of sub-pixel areas to define each sub-pixel area. The color filter may further include a light blocking pattern located between the plurality of color filter areas.

The plurality of color filter areas may include: a first color filter area emitting first color light; a second color filter area emitting second color light; and/or a third color filter area emitting a third color light, and the first color light, the second color light, and/or the third color light may have different maximum emission wavelengths. In some exemplary embodiments, the first color light may be red light, the second color light may be green light, and the third color light may be blue light, but the exemplary embodiments are not limited thereto. In some exemplary embodiments, the plurality of color filter areas may each include a quantum dot, but the exemplary embodiments are not limited thereto. In some exemplary embodiments, the first color filter area may include a red quantum dot, the second color filter area may include a green quantum dot, and the third color filter area may not include a quantum dot. The quantum dot may be understood by referring to the description of the quantum dot provided herein. The first color filter area, the second color filter area, and/or the third color filter area may each further include an emitter, but the exemplary embodiments are not limited thereto.

In some exemplary embodiments, the light-emitting device may emit first light, the first color filter area may absorb the first light to emit a 1-1 color light, the second color filter area may absorb the first light to emit a 2-1 color light, and the third color filter area may absorb the first light to emit a 3-1 color light. In this exemplary embodiment, the 1-1 color light, the 2-1 color light, and the 3-1 color light may each have a different maximum emission wavelength. In some exemplary embodiments, the first light may be blue light, the 1-1 color light may be red light, the 2-1 color light may be green light, and the 3-1 light may be blue light, but the exemplary embodiments are not limited thereto.

The emission apparatus may further include a thin film transistor, in addition to the light-emitting device. The thin film transistor may include a source electrode, a drain electrode, and an activation layer, wherein one of the source electrode and the drain electrode may be electrically connected to one of the first electrode and the second electrode of the light-emitting device.

The thin-film transistor may further include a gate electrode, a gate insulating film, or the like. The activation layer may include a crystalline silicon, an amorphous silicon, an organic semiconductor, and an oxide semiconductor, but the exemplary embodiments are not limited thereto. The emission apparatus may further include a sealing portion for sealing the light-emitting device. The sealing portion may be located between the color filter and the light-emitting device. The sealing portion may allow light to pass to the outside from the light-emitting device and prevent the air and moisture to permeate to the light-emitting device at the same time. The sealing portion may be a sealing substrate including a transparent glass or a plastic substrate. The sealing portion may be a thin film encapsulating layer including a plurality of organic layers and/or a plurality of inorganic layers. When the sealing portion is a thin film encapsulating layer, the emission apparatus may be flexible. The emission apparatus may be used in various displays, light sources, or the like.

The authentication apparatus may be, for example, a biometric authentication apparatus that identifies an individual according biometric information (e.g., a fingertip, a pupil, or the like). The authentication apparatus may further include a biometric information collecting unit, in addition to the light-emitting device described above. The electronic apparatus may be applicable to a personal computer (e.g., a mobile personal computer), a cellphone, a digital camera, an electronic note, an electronic dictionary, an electronic game console, a medical device (e.g., an electronic thermometer, a blood pressure meter, a glucometer, a pulse measuring device, a pulse wave measuring device, an electrocardiograph recorder, an ultrasonic diagnosis device, an endoscope display device), a fish finder, various measurement devices, gauges (e.g., gauges of an automobile, an airplane, a ship), a projector, but the exemplary embodiments are not limited thereto.

Manufacturing Method

The layers constituting the hole transport region, the emission layer, and the layers constituting the electron transport region may be formed in a specific region by using one or more suitable methods such as vacuum deposition, spin coating, casting, Langmuir-Blodgett (LB) deposition, ink-jet printing, laser printing, and laser-induced thermal imaging.

When layers constituting the hole transport region, an emission layer, and layers constituting the electron transport region are each independently formed by vacuum-deposition, the vacuum-deposition may be performed at a deposition temperature in a range of about 100° C. to about 500° C., at a vacuum degree in a range of about 10⁻⁸ torr to about 10⁻³ torr, and at a deposition rate in a range of about 0.01 Angstroms per second (A/sec) to about 100 Å/sec, depending on the material to be included in each layer and the structure of each layer to be formed.

When layers constituting the hole transport region, the emission layer, and layers constituting the electron transport region are each independently formed by spin coating, the spin coating may be performed at a coating rate of about 2,000 revolutions per minute (rpm) to about 5,000 rpm and at a heat treatment temperature of about 80° C. to 200° C., depending on the material to be included in each layer and the structure of each layer to be formed.

General Definitions

The term “interlayer” as used herein refers to a single layer and/or a plurality of layers between the first electrode and the second electrode in a light-emitting device. A material included in the “interlayer” is not limited to an organic material. The expression “(interlayer) includes at least one compound” as used herein may be construed as meaning the “(interlayer) may include one compound of Formula 1 or two different compounds of Formula 1”.

The term “π electron deficient nitrogen-containing cyclic group” as used herein refers to a C₁-C₆₀ heterocyclic group having at least one *—N═*′ moiety as a ring-forming moiety.

The term “quantum dot” as used herein refers to a crystal of a semiconductor compound and may include any material emitting emission wavelengths of different lengths according to the size of the crystal. Accordingly, the material for the quantum dot is not particularly limited. The diameter of the quantum dot is not particularly limited. The diameter may be, for example, in a range of about 1 nanometer (nm) to about 10 nm.

The term “C₁-C₆₀ alkyl group” as used herein refers to a linear or branched aliphatic hydrocarbon monovalent group having 1 to 60 carbon atoms, and examples thereof include a methyl group, an ethyl group, an n-propyl group, an iso-propyl group, an n-butyl group, a sec-butyl group, an isobutyl group, a tert-butyl group, an n-pentyl group, a tert-pentyl group, a neopentyl group, an isopentyl group, a sec-pentyl group, a 3-pentyl group, a sec-isopentyl group, an n-hexyl group, an iso-hexyl group, a sec-hexyl group, a tert-hexyl group, an n-heptyl group, an iso-heptyl group, a sec-heptyl group, a tert-heptyl group, an n-octyl group, an iso-octyl group, a sec-octyl group, a tert-octyl group, an n-nonyl group, an iso-nonyl group, a sec-nonyl group, a tert-nonyl group, an n-decyl group, an iso-decyl group, a sec-decyl group, and a tert-decyl group. The term “C₁-C₆₀ alkylene group” as used herein refers to a divalent group having a structure corresponding to the C₁-C₆₀ alkyl group.

The term “C₂-C₆₀ alkenyl group” as used herein refers to a hydrocarbon group having at least one carbon-carbon double bond in the middle or at the terminus of the C₂-C₆₀ alkyl group. Examples thereof include an ethenyl group, a propenyl group, and a butenyl group. The term “C₂-C₆₀ alkenylene group” as used herein refers to a divalent group having a structure corresponding to the C₂-C₆₀ alkenyl group.

The term “C₂-C₆₀ alkynyl group” as used herein refers to a monovalent hydrocarbon group having at least one carbon-carbon triple bond in the middle or at the terminus of the C₂-C₆₀ alkyl group. Examples thereof include an ethynyl group and a propynyl group. The term “C₂-C₆₀ alkynylene group” as used herein refers to a divalent group having a structure corresponding to the C₂-C₆₀ alkynyl group.

The term “C₁-C₆₀ alkoxy group” as used herein refers to a monovalent group represented by —OA₁₀₁ (wherein A₁₀₁ is a C₁-C₁ alkyl group). Examples thereof include a methoxy group, an ethoxy group, and an isopropyloxy group.

The term “C₃-C₁₀ cycloalkyl group” as used herein refers to a monovalent saturated hydrocarbon monocyclic group including 3 to 10 carbon atoms. Examples of the C₃-C₁₀ cycloalkyl group as used herein include a cyclopropyl group, a cyclobutyl group, a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, a cyclooctyl group, an adamantanyl group, a norbomanyl group, a bicyclo[1.1.1]pentyl group, a bicyclo[2.1.1]hexyl group, a bicyclo[2.2.1]heptyl group, or a bicyclo[2.2.2]octyl group. The term “C₃-C₁₀ cycloalkylene group” as used herein refers to a divalent group having a structure corresponding to the C₃-C₁₀ cycloalkyl group.

The term “C₁-C₁₀ heterocycloalkyl group” as used herein refers to a monovalent cyclic group including a heteroatom (e.g., N, O, Si, P, S, or any combination thereof) as a ring-forming atom and 1 to 10 carbon atoms. Examples thereof include a 1,2,3,4-oxatriazolidinyl group, a tetrahydrofuranyl group, and a tetrahydrothiophenyl group. The term “C₁-C₁₀ heterocycloalkylene group” as used herein refers to a divalent group having a structure corresponding to the C₁-C₁₀ heterocycloalkyl group.

The term “C₃-C₁₀ cycloalkenyl group” as used herein refers to a monovalent cyclic group that has 3 to 10 carbon atoms and at least one carbon-carbon double bond in its ring, and is not aromatic. Examples thereof include a cyclopentenyl group, a cyclohexenyl group, and a cycloheptenyl group. The term “C₃-C₁₀ cycloalkenylene group” as used herein refers to a divalent group having a structure corresponding to the C₃-C₁₀ cycloalkenyl group.

The term “C₁-C₁₀ heterocycloalkenyl group” as used herein refers to a monovalent cyclic group including a heteroatom (e.g., N, O, Si, P, S, or any combination thereof) as a ring-forming atom, 1 to 10 carbon atoms, and at least one double bond in its ring. Examples of the C₁-C₁₀ heterocycloalkenyl group include a 4,5-dihydro-1,2,3,4-oxatriazolyl group, a 2,3-dihydrofuranyl group, and a 2,3-dihydrothiophenyl group. The term “C₁-C₁₀ heterocycloalkylene group” as used herein refers to a divalent group having a structure corresponding to the C₁-C₁₀ heterocycloalkenyl group.

The term “C₆-C₆₀ aryl group” as used herein refers to a monovalent group having a carbocyclic aromatic system having 6 to 6 carbon atoms. The term “C₆-C₆₀ arylene group” as used herein refers to a divalent group having a carbocyclic aromatic system having 6 to 60 carbon atoms. Examples of the C₆-C₆₀ aryl group include a phenyl group, a pentalenyl group, a naphthyl group, an azulenyl group, an indacenyl group, an acenaphthyl group, a phenalenyl group, a phenanthrenyl group, an anthracenyl group, a fluoranthenyl group, a triphenylenyl group, a pyrenyl group, a chrysenyl group, a perylenyl group, a pentaphenyl group, a heptalenyl group, a naphthacenyl group, a picenyl group, a hexacenyl group, a pentacenyl group, a rubicenyl group, a coronenyl group, and an ovalenyl group. When the C₆-C₆₀ aryl group and the C₆-C₆₀ arylene group each independently include two or more rings, the respective rings may be fused.

The term “C₁-C₆₀ heteroaryl group” as used herein refers to a monovalent group having a heterocyclic aromatic system having a heteroatom (e.g., N, O, Si, P, S, or any combination thereof) as a ring-forming atom and 1 to 60 carbon atoms. The term “C₁-C₆₀ heteroarylene group” as used herein refers to a divalent group having a heterocyclic aromatic system having a heteroatom (e.g., N, O, Si, P, S, or any combination thereof) as a ring-forming atom and 1 to 60 carbon atoms. Examples of the C₁-C₆₀ heteroaryl group include a pyridinyl group, a pyrimidinyl group, a pyrazinyl group, a pyridazinyl group, a triazinyl group, a quinolinyl group, a benzoquinolinyl group, an isoquinolinyl group, a benzoisoquinolinyl group, a quinoxalinyl group, a benzoquinoxalinyl group, a quinazolinyl group, a benzoquinazolinyl group, a cinnolinyl group, a phenanthrolinyl group, a phthalazinyl group, and a naphthyridinyl group. When the C₁-C₆₀ heteroaryl group and the C₁-C₆₀ heteroarylene group each independently include two or more rings, the respective rings may be fused.

The term “C₆-C₆₀ aryloxy group” as used herein is represented by —OA₁₀₂ (wherein A₁₀₂ is the C₆-C₆₀ aryl group). The term “C₆-C₆₀ arylthio group” as used herein is represented by —SA₁₀₃ (wherein A₁₀₃ is the C₆-C₆₀ aryl group).

The term “monovalent non-aromatic fused polycyclic group” as used herein refers to a monovalent group that has two or more rings fused and only carbon atoms as ring forming atoms (e.g., 8 to 60 carbon atoms), wherein the entire molecular structure is non-aromatic. Examples of the monovalent non-aromatic fused polycyclic group include an indenyl group, a fluorenyl group, a spiro-bifluorenyl group, a benzofluorenyl group, an indenophenanthrenyl group, and an indenoanthracenyl group. The term “divalent non-aromatic fused polycyclic group” as used herein refers to a divalent group having substantially the same structure as the monovalent non-aromatic fused polycyclic group.

The term “monovalent non-aromatic fused heteropolycyclic group” as used herein refers to a monovalent group that has two or more rings fused, and has a heteroatom (N, O, Si, P, S, or any combination thereof) as ring-forming atoms other than carbon atoms, wherein the molecular structure as a whole is non-aromatic in the entire molecular structure. Examples of the monovalent non-aromatic fused heteropolycyclic group include a pyrrolyl group, a thiophenyl group, a furanyl group, an indolyl group, a benzoindolyl group, a naphthoindolyl group, an isoindolyl group, a benzoisoindolyl group, a naphthoisoindolyl group, a benzosilolyl group, a benzothiophenyl group, a benzofuranyl group, a carbazolyl group, a dibenzosilolyl group, a dibenzothiophenyl group, a dibenzofuranyl group, an azacarbazolyl group, an azafluorenyl group, an azadibenzosilolyl group, an azadibenzothiophenyl group, an azadibenzofuranyl group, a pyrazolyl group, an imidazolyl group, a triazolyl group, a tetrazolyl group, an oxazolyl group, an isoxazolyl group, a thiazolyl group, an isothiazolyl group, an oxadiazolyl group, a thiadiazolyl group, a benzopyrazolyl group, a benzimidazolyl group, a benzoxazolyl group, a benzothiazolyl group, a benzooxadiazolyl group, a benzothiadiazolyl group, an imidazopyridinyl group, an imidazopyrimidinyl group, an imidazotriazinyl group, an imidazopyrazinyl group, an imidazopyridazinyl group, an indenocarbazolyl group, an indolocarbazolyl group, a benzofurocarbazolyl group, a benzothienocarbazolyl group, a benzosilolocarbazolyl group, a benzoindolocarbazolyl group, a benzocarbazolyl group, a benzonaphthofuranyl group, a benzonaphthothiophenyl group, a benzonaphthosilolyl group, a benzofurodibenzofuranyl group, a benzofurodibenzothiophenyl group, and a benzothienodibenzothiophenyl group. The term “divalent non-aromatic fused heteropolycyclic group” as used herein refers to a divalent group having a structure corresponding to the monovalent non-aromatic fused heteropolycyclic group.

The term “C₅-C₆₀ carbocyclic group” as used herein refers to a monocyclic or polycyclic group having 5 to 60 carbon atoms only as ring-forming atoms. The C₅-C₆₀ carbocyclic group may be an aromatic carbocyclic group or a non-aromatic carbocyclic group. The term “C₅-C₆₀ carbocyclic group” as used herein refers to a compound (e.g., a benzene group), a monovalent group (e.g., a phenyl group), or a divalent group (e.g., a phenylene group). Also, depending on the number of substituents connected to the C₅-C₆₀ carbocyclic group, the C₅-C₆₀ carbocyclic group may be a trivalent group or a quadrivalent group. Examples of the C₅-C₆₀ carbocyclic group include a cyclopentadiene group, a benzene group, a pentalene group, a naphthalene group, an azulene group, an indacene group, an acenaphthylene group, a phenalene group, a phenanthrene group, an anthracene group, a fluoranthene group, a triphenylene group, a pyrene group, a chrysene group, a perylene group, a pentaphene group, a heptalene group, a naphthacene group, a picene group, a hexacene group, a pentacene group, a rubicene group, a coronene group, an ovalene group, an indene group, a fluorene group, a spiro-bifluorene group, a benzofluorene group, an indenophenanthrene group, and an indenoanthracene group.

The term “C₁-C₆₀ heterocyclic group” as used herein refers to a monocyclic or polycyclic group which includes 1 to 60 carbon atoms and as ring-forming atoms, a heteroatom (e.g., N, O, Si, P, S, or any combination thereof), in addition to carbon atoms. The C₁-C₆₀ heterocyclic group may be an aromatic heterocyclic group or a non-aromatic heterocyclic group. The term “C₁-C₆₀ heterocyclic group” as used herein refers to a compound (e.g., a pyridine group), a monovalent group (e.g., a pyridinyl group), or a divalent group (e.g., a pyridinylene group). Also, depending on the number of substituents connected to the C₁-C₆₀ heterocyclic group, the C₁-C₆₀ heterocyclic group may be a trivalent group or a quadrivalent group.

Examples of the C₁-C₆₀ heterocyclic group include a pyridine group, a pyrimidine group, a pyrazine group, a pyridazine group, a triazine group, a quinoline group, a benzoquinoline group, an isoquinoline group, a benzoisoquinoline group, a quinoxaline group, a benzoquinoxaline group, a quinazoline group, a benzoquinazoline group, a cinnoline group, a phenanthroline group, a phthalazine group, a naphthyridine group, a pyrrole group, a thiophene group, a furan group, an indole group, a benzoindole group, a naphthoindole group, an isoindole group, a benzoisoindole group, a naphthoisoindole group, a benzosilole group, a benzothiophene group, a benzofuran group, a carbazole group, a dibenzosilole group, a dibenzothiophene group, a dibenzofuran group, an azacarbazole group, an azafluorene group, an azadibenzosilole group, an azadibenzothiophene group, an azadibenzofuran group, a pyrazole group, an imidazole group, a triazole group, a tetrazole group, an oxazole group, an isooxazole group, a thiazole group, an isothiazole group, an oxadiazole group, a thiadiazole group, a benzopyrazole group, a benzimidazole group, a benzoxazole group, a benzothiazole group, a benzoxadiazole group, a benzothiadiazole group, an imidazopyridine group, an imidazopyrimidine group, an imidazotriazine group, an imidazopyrazine group, an imidazopyridazine group, an indenocarbazole group, an indolocarbazole group, a benzofurocarbazole group, a benzothienocarbazole group, a benzosilolocarbazole group, a benzoindolocarbazole group, a benzocarbazole group, a benzonaphthofuran group, a benzonapthothiophene group, a benzonaphthosilole group, a benzofurodibenzofuran group, a benzofurodibenzothiophene group, and a benzothienodibenzothiophene group.

As used herein, the term “atom” may mean an element or its corresponding radical bonded to one or more other atoms.

The terms “hydrogen” and “deuterium” refer to their respective atoms and corresponding radicals, and the terms “—F, —Cl, —Br, and —I” are radicals of, respectively, fluorine, chlorine, bromine, and iodine.

As used herein, a substituent for a monovalent group, e.g., alkyl, may also be, independently, a substituent for a corresponding divalent group, e.g., alkylene.”

As described herein, a substituent of the substituted C₅-C₆₀ carbocyclic group, the substituted C₁-C₆₀ heterocyclic group, the substituted C₁-C₆₀ alkylene group, the substituted C₂-C₆₀ alkenylene group, the substituted C₃-C₁₀ cycloalkylene group, the substituted C₁-C₁₀ heterocycloalkylene group, the substituted C₃-C₁₀ cycloalkenylene group, the substituted C₁-C₁₀ heterocycloalkenylene group, the substituted C₆-C₆₀ arylene group, the substituted C₁-C₆₀ heteroarylene group, the substituted divalent non-aromatic fused polycyclic group, the substituted divalent non-aromatic fused heteropolycyclic group, the substituted C₁-C₆₀ alkyl group, the substituted C₂-C₆₀ alkenyl group, the substituted C₂-C₆₀ alkynyl group, the substituted C₁-C₆₀ alkoxy group, the substituted C₃-C₁₀ cycloalkyl group, the substituted C₁-C₁₀ heterocycloalkyl group, the substituted C₃-C₁₀ cycloalkenyl group, the substituted C₁-C₁₀ heterocycloalkenyl group, the substituted C₆-C₆₀ aryl group, the substituted C₆-C₆₀ aryloxy group, the substituted C₆-C₆₀ arylthio group, the substituted C₁-C₆₀ heteroaryl group, the substituted monovalent non-aromatic fused polycyclic group, and substituted monovalent non-aromatic fused heteropolycyclic group may be:

-   -   deuterium (-D), —F, —Cl, —Br, —I, a hydroxyl group, a cyano         group, or a nitro group;     -   a C₁-C₆₀ alkyl group, a C₂-C₆₀ alkenyl group, a C₂-C₆₀ alkynyl         group, or a C₁-C₆₀ alkoxy group, each unsubstituted or         substituted with at least one selected from deuterium, —F, —Cl,         —Br, —I, a hydroxyl group, a cyano group, a nitro group, a         C₃-C₁₀ cycloalkyl group, a C₁-C₁₀ heterocycloalkyl group, a         C₃-C₁₀ cycloalkenyl group, a C₁-C₁₀ heterocycloalkenyl group, a         C₆-C₆₀ aryl group, a C₆-C₆₀ aryloxy group, a C₆-C₆₀ arylthio         group, a C₁-C₆₀ heteroaryl group, a monovalent non-aromatic         fused polycyclic group, a monovalent non-aromatic fused         heteropolycyclic group, —Si(Q₁₁)(Q₁₂)(Q₁₃), —N(Q₁₁)(Q₁₂),         —B(Q₁₁)(Q₁₂), —C(═O)(Q₁₁), —S(═O)₂(Q₁₁), and —P(═O)(Q₁₁)(Q₁₂);     -   a C₃-C₁₀ cycloalkyl group, a C₁-C₁₀ heterocycloalkyl group, a         C₃-C₁₀ cycloalkenyl group, a C₁-C₁₀ heterocycloalkenyl group, a         C₆-C₆₀ aryl group, a C₆-C₆₀ aryloxy group, a C₆-C₆₀ arylthio         group, a C₁-C₆₀ heteroaryl group, a monovalent non-aromatic         fused polycyclic group, or a monovalent non-aromatic fused         heteropolycyclic group, each unsubstituted or substituted with         at least one selected from deuterium, —F, —Cl, —Br, —I, a         hydroxyl group, a cyano group, a nitro group, a C₁-C₆₀ alkyl         group, a C₂-C₆₀ alkenyl group, a C₂-C₆₀ alkynyl group, a C₁-C₆₀         alkoxy group, a C₃-C₁₀ cycloalkyl group, a C₁-C₁₀         heterocycloalkyl group, a C₃-C₁₀ cycloalkenyl group, a C₁-C₁₀         heterocycloalkenyl group, a C₆-C₆₀ aryl group, a C₆-C₆₀ aryloxy         group, a C₆-C₆₀ arylthio group, a C₁-C₆₀ heteroaryl group, a         monovalent non-aromatic fused polycyclic group, a monovalent         non-aromatic fused heteropolycyclic group, —Si(Q₂₁)(Q₂₂)(Q₂₃),         —N(Q₂₁)(Q₂₂), —B(Q₂₁)(Q₂₂), —C(═O)(Q₂₁), —S(═O)₂(Q₂₁), and         —P(═O)(Q₂₁)(Q₂₂);     -   —Si(Q₃₁)(Q₃₂)(Q₃₃), —N(Q₃₁)(Q₃₂), —B(Q₃₁)(Q₃₂), —C(═O)(Q₃₁),         —S(═O)₂(Q₃₁), or —P(═O)(Q₃₁)(Q₃₂), or any combination thereof.

As described herein, Q₁ to Q₃, Q₁₁ to Q₁₁, Q₂₁ to Q₂₃, and Q₃₁ to Q₃₃ may each independently be hydrogen, deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, a C₁-C₆₀ alkyl group, a C₂-C₆₀ alkenyl group, a C₂-C₆₀ alkynyl group, a C₁-C₆₀ alkoxy group, a C₃-C₁₀ cycloalkyl group, a C₁-C₁₀ heterocycloalkyl group, a C₃-C₁₀ cycloalkenyl group, a C₁-C₁₀ heterocycloalkenyl group, a C₆-C₆₀ aryl group, a C₁-C₆₀ heteroaryl group, a monovalent non-aromatic fused polycyclic group, a monovalent non-aromatic fused heteropolycyclic group, a biphenyl group, or a terphenyl group. “Ph” used herein represents a phenyl group, “Me” used herein represents a methyl group, “Et” used herein represents an ethyl group, “ter-Bu” or “Bu^(t)” used herein represents a tert-butyl group, and “OMe” used herein represents a methoxy group.

The term “biphenyl group” as used herein refers to a phenyl group substituted with at least one phenyl group. The “biphenyl group” belongs to “a substituted phenyl group” having a “C₆-C₆₀ aryl group” as a substituent.

The term “terphenyl group” as used herein refers to a phenyl group substituted with at least one phenyl group. The “terphenyl group” belongs to “a substituted phenyl group” having a “C₆-C₆₀ aryl group substituted with a C₆-C₆₀ aryl group” as a substituent.

The symbols * and *′ as used herein, unless defined otherwise, refer to a binding site to an adjacent atom in a corresponding formula.

Hereinafter, compounds and a light-emitting device according to one or more exemplary embodiments will be described in more detail with reference to Synthesis Examples and Examples. The wording “B was used instead of A” used in describing Synthesis Examples means that an amount of B used was identical to an amount of A used in terms of molar equivalents.

EXAMPLES

Preparation of Compound

Preparation of Compound 1

(1) Synthesis of Compound 1

0.42 grams (g) of Condensed Polycyclic Compound 1 was synthesized according to Reaction Scheme 1 using 4.47 g (10 mmol) of 1,2-bis(3-phenoxyphenoxy)benzene and 4.82 milliliters (mL, 50 mmol) of BBr₃ (yield: 9%).

(2) Synthesis of Compound 2

0.64 g of Condensed Polycyclic Compound 2 was synthesized according to Reaction Scheme 2 using 5.22 g (10 mmol) of Intermediate 3-(2-(3-phenoxyphenoxy)phenoxy)-N,N-diphenylaniline prepared with 3-phenoxyphenol made in Reaction Scheme 1 and 4.82 mL (50 mmol) of BBr₃ (yield: 12%).

(3) Synthesis of Compound 9

0.67 g of Condensed Polycyclic Compound 9 was synthesized according to Reaction Scheme 4 using 5.95 g (10 mmol) of 2-(3-(9H-carbazol-9-yl)phenoxy)-N-(3-phenoxyphenyl)-N-phenylaniline prepared using Intermediate 9-1 synthesized according to Reaction Scheme 3 and 4.82 mL (50 mmol) of BBr₃ (yield: 11%).

(3) Synthesis of Compound 21

Reaction Scheme 5

1.41 g of Condensed Polycyclic Compound 21 was synthesized according to Reaction Scheme 5 using 9.27 g (10 mmol) of 5,5′-(1,2-phenylenebis(oxy))bis(3-(9H-carbazol-9-yl)-N,N-diphenylaniline) and 4.82 mL (50 mmol) of BBr₃ (yield: 15%).

Manufacture of Organic Light-Emitting Device

EXAMPLES AND COMPARATIVE EXAMPLES

Organic Light-emitting devices including the Condensed Polycyclic Compounds in the emission layer were manufactured according to the following method. Organic light-emitting devices of Examples 1 to 4 were manufactured using the Condensed Polycyclic Compounds as dopant materials of the emission layer. Organic light-emitting devices of Comparative Examples 1 to 4 were respectively manufactured using Comparative Example Compound DPS and Comparative Example Compounds 100 to 102 as dopant materials of the emission layer.

An ITO was patterned on a glass substrate at a thickness of 1,200 Å, and the glass substrate was sonicated by using isopropyl alcohol and deionized water for 5 minutes, respectively, cleaned by exposure to ultraviolet rays for 30 minutes, and then treated with ozone. Subsequently, NPD was vacuum-deposited thereon at a thickness of 300 Å to form a hole injection layer, TCTA was vacuum-deposited thereon at a thickness of 200 Å, and 9-[4-(1,1-dimethylethyl)phenyl]-3,6-bis(triphenylsilyl)-9H-carbazole (CzSi) was vacuum-deposited thereon at a thickness of 100 Å, thereby forming a hole transport layer.

A compound mCP and the Condensed Polycyclic Compound or the Comparative Example Compound were co-deposited at a ratio of 99:1 on the hole transport layer to form an emission layer having a thickness of 200 Å. In Examples 1 to 4, the emission layers were respectively co-deposited using mCP and Compounds 1, 2, 9, and 21. In Comparative Examples 1 to 4, the emission layers were respectively co-deposited using mCP and Comparative Example Compound having a diphenyl sulfone moiety (DPS) and Comparative Example Compounds 100 to 102.

A diphenyl-4-triphenylsilylphenyl-phosphine oxide (TPSOl) material was deposited on the emission layer to form an electron transport layer having a thickness of 200 Å, and subsequently, a compound (2,2′,2″-(1,3,5-Benzinetriyl)-tris(1-phenyl-1-H-benzimidazole)) TPBi at a thickness of 300 Å and LiF at a thickness of 10 Å were sequentially deposited thereon to form an electron injection layer. Aluminum (Al) was deposited on the electron injection layer at a thickness of 3,000 Å to form a second electrode.

The compound CP5 was vacuum-deposited on the second electrode to form a capping layer having a thickness of 700 Å.

Compounds used in the manufacture of organic light-emitting devices of the Examples and the Comparative Examples are shown herein.

The luminescence efficiency of each light-emitting device of Examples 1 to 4 and Comparative Examples 1 to 4 was measured using a luminance meter sold under the trade designation PR650 from Konica Minolta, Inc. of Tokyo, Japan, at a brightness of 700 nit. The results thereof are shown in Table 1.

TABLE 1 Luminescence Driving voltage efficiency Host: Dopant (cd/A) (cd/A) Example 1 mCP: 1 5.5 20.7 Example 2 mCP: 2 5.3 19.1 Example 3 mCP: 9 5.2 21.3 Example 4 mCP: 21 4.9 23.8 Comparative mCP: DPS 5.8 15.4 Example 1 Comparative mCP: 100 6.1 17.6 Example 2 Comparative mCP: 101 5.6 18.3 Example 3 Comparative mCP: 102 5.9 17.9 Example 4

As shown in Table 1, the light-emitting devices of Examples 1 to 4 were found to exhibit significant and surprisingly excellent results, as compared with the light-emitting devices of Comparative Examples 1 to 4.

When the compound represented by Formula 1 according to the principles and exemplary embodiments of the invention is used as a material for an emission layer, a light-emitting device including the compound has significantly and surprisingly decreased driving voltage and improved efficiency, as compared to compounds known in the related art. Particularly, the half lifespan of luminescence of the light-emitting device constructed according to the principles and exemplary embodiments of the invention may increase.

Although certain exemplary embodiments and implementations have been described herein, other embodiments and modifications will be apparent from this description. Accordingly, the inventive concepts are not limited to such embodiments, but rather to the broader scope of the appended claims and various obvious modifications and equivalent arrangements as would be apparent to a person of ordinary skill in the art. 

What is claimed is:
 1. A light-emitting device comprising: a first electrode; a second electrode facing the first electrode; and an intermediate layer disposed between the first electrode and the second electrode and comprising an emission layer, wherein the first electrode includes indium tin oxide (ITO), indium zinc oxide (IZO), tin oxide (SnO₂), zinc oxide (ZnO), magnesium (Mg), silver (Ag), aluminum (Al), aluminum-lithium (Al—Li), calcium (Ca), magnesium-indium (Mg—In), magnesium-silver (Mg—Ag) or any combination thereof and the second electrode includes lithium (Li), silver (Ag), magnesium (Mg), aluminum (Al), aluminum-lithium (Al—Li), calcium (Ca), magnesium-indium (Mg—In), magnesium-silver (Mg—Ag), indium tin oxide (ITO), indium zinc oxide (IZO) or any combination thereof, the intermediate layer comprises the compound of Formula 1:

wherein, in Formula 1: X₁ to X₄ are each, independently from one another, O, S, NR₂₁, or CR₂₂R₂₃; R₁ to R₁₆ and R₂₁ to R₂₃ are each, independently from one another, hydrogen, deuterium, a substituted or unsubstituted C₁-C₆₀ alkyl group, a substituted or unsubstituted C₂-C₆₀ alkenyl group, a substituted or unsubstituted C₂-C₆₀ alkynyl group, a substituted or unsubstituted C₁-C₆₀ alkoxy group, a substituted or unsubstituted C₃-C₁₀ cycloalkyl group, a substituted or unsubstituted C₁-C₁₀ heterocycloalkyl group, a substituted or unsubstituted C₃-C₁₀ cycloalkenyl group, a substituted or unsubstituted C₁-C₁₀ heterocycloalkenyl group, a substituted or unsubstituted C₆-C₆₀ aryl group, a substituted or unsubstituted C₆-C₆₀ aryloxy group, a substituted or unsubstituted C₆-C₆₀ arylthio group, a substituted or unsubstituted C₁-C₆₀ heteroaryl group, a substituted or unsubstituted monovalent non-aromatic fused polycyclic group, a substituted or unsubstituted monovalent non-aromatic fused heteropolycyclic group, —Si(Q₁)(Q₂)(Q₃), —N(Q₁)(Q₂), —P(Q₁)(Q₂), —C(═O)(Q₁), —S(═O)₂(Q₁), or —P(═O)(Q₁)(Q₂), wherein adjacent substituents in R₁ to R₁₆ and R₂₁ to R₂₃ are linked to each other to form a ring; and at least one substituent of the substituted C₁-C₆₀ alkyl group, the substituted C₂-C₆₀ alkenyl group, the substituted C₂-C₆₀ alkynyl group, the substituted C₁-C₆₀ alkoxy group, the substituted C₃-C₁₀ cycloalkyl group, the substituted C₁-C₁₀ heterocycloalkyl group, the substituted C₃-C₁₀ cycloalkenyl group, the substituted C₁-C₁₀ heterocycloalkenyl group, the substituted C₆-C₆₀ aryl group, the substituted C₆-C₆₀ aryloxy group, the substituted C₆-C₆₀ arylthio group, the substituted C₁-C₆₀ heteroaryl group, the substituted monovalent non-aromatic fused polycyclic group, and the substituted monovalent non-aromatic fused heteropolycyclic group is: deuterium (-D), —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an amidino group, a hydrazino group, a hydrazono group, a C₁-C₆₀ alkyl group, a C₂-C₆₀ alkenyl group, a C₂-C₆₀ alkynyl group, and a C₁-C₆₀ alkoxy group; a C₁-C₆₀ alkyl group, a C₂-C₆₀ alkenyl group, a C₂-C₆₀ alkynyl group, and a C₁-C₆₀ alkoxy group, each substituted with at least one of deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an amidino group, a hydrazino group, a hydrazono group, a C₃-C₁₀ cycloalkyl group, a C₁-C₁₀ heterocycloalkyl group, a C₃-C₁₀ cycloalkenyl group, a C₁-C₁₀ heterocycloalkenyl group, a C₆-C₆₀ aryl group, a C₆-C₆₀ aryloxy group, a C₆-C₆₀ arylthio group, a C₁-C₆₀ heteroaryl group, a monovalent non-aromatic fused polycyclic group, a monovalent non-aromatic fused heteropolycyclic group, —Si(Q₁₁)(Q₁₂)(Q₁₃), —N(Q₁₁)(Q₁₂), —P(Q₁₁)(Q₁₂), —C(═O)(Q₁₁), —S(═O)₂(Q₁₁), and —P(═O)(Q₁₁)(Q₁₂); a C₃-C₁₀ cycloalkyl group, a C₁-C₁₀ heterocycloalkyl group, a C₃-C₁₀ cycloalkenyl group, a C₁-C₁₀ heterocycloalkenyl group, a C₆-C₆₀ aryl group, a C₆-C₆₀ aryloxy group, a C₆-C₆₀ arylthio group, a C₁-C₆₀ heteroaryl group, a monovalent non-aromatic fused polycyclic group, and a monovalent non-aromatic fused heteropolycyclic group; a C₃-C₁₀ cycloalkyl group, a C₁-C₁₀ heterocycloalkyl group, a C₃-C₁₀ cycloalkenyl group, a C₁-C₁₀ heterocycloalkenyl group, a C₆-C₆₀ aryl group, a C₆-C₆₀ aryloxy group, a C₆-C₆₀ arylthio group, a C₁-C₆₀ heteroaryl group, a monovalent non-aromatic fused polycyclic group, and a monovalent non-aromatic fused heteropolycyclic group, each substituted with at least one of deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an amidino group, a hydrazino group, a hydrazono group, a C₁-C₆₀ alkyl group, a C₂-C₆₀ alkenyl group, a C₂-C₆₀ alkynyl group, a C₁-C₆₀ alkoxy group, a C₃-C₁₀ cycloalkyl group, a C₁-C₁₀ heterocycloalkyl group, a C₃-C₁₀ cycloalkenyl group, a C₁-C₁₀ heterocycloalkenyl group, a C₆-C₆₀ aryl group, a C₆-C₆₀ aryloxy group, a C₆-C₆₀ arylthio group, a C₁-C₆₀ heteroaryl group, a monovalent non-aromatic fused polycyclic group, a monovalent non-aromatic fused heteropolycyclic group, —Si(Q₂₁)(Q₂₂)(Q₂₃), —N(Q₂₁)(Q₂₂), —P(Q₂₁)(Q₂₂), —C(═O)(Q₂₁), —S(═O)₂(Q₂₁), and —P(═O)(Q₂₁)(Q₂₂); and —Si(Q₃₁)(Q₃₂)(Q₃₃), —N(Q₃₁)(Q₃₂), —P(Q₃₁)(Q₃₂), —C(═O)(Q₃₁), —S(═O)₂(Q₃₁), and —P(═O)(Q₃₁)(Q₃₂), wherein Q₁ to Q₃, Q₁₁ to Q₁₃, Q₂₁ to Q₂₃, and Q₃₁ to Q₃₃ are each, independently from one another, of hydrogen, deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an amidino group, a hydrazino group, a hydrazono group, a C₁-C₆₀ alkyl group, a C₂-C₆₀ alkenyl group, a C₂-C₆₀ alkynyl group, a C₁-C₆₀ alkoxy group, a C₃-C₁₀ cycloalkyl group, a C₁-C₁₀ heterocycloalkyl group, a C₃-C₁₀ cycloalkenyl group, a C₁-C₁₀ heterocycloalkenyl group, a C₆-C₆₀ aryl group, a C₁-C₆₀ heteroaryl group, a monovalent non-aromatic fused polycyclic group, a monovalent non-aromatic fused heteropolycyclic group, a biphenyl group, or a terphenyl group.
 2. The organic light-emitting device of claim 1, R₁₅ and R₁₆ are each, independently from one another, hydrogen or deuterium.
 3. The organic light-emitting device of claim 1, wherein two adjacent substituents of R₁ to R₁₄ and R₂₁ to R₂₃ are linked to each other to form a ring.
 4. The organic light-emitting device of claim 1, wherein X₂ and X₃ are each, independently from one another, O, S, or NR₂₁.
 5. The organic light-emitting device of claim 1, wherein X₁ and X₄ are each, independently from one another, O, NR₂₁, or CR₂₂R₂₃.
 6. The organic light-emitting device of claim 1, wherein R₁ to R₁₄ and R₂₁ to R₂₃ are each, independently from one another, hydrogen, deuterium, a substituted or unsubstituted C₁-C₆₀ alkyl group, or a moiety represented by one of Formulae 2a to 2g:

wherein, in Formulae 2a to 2g, R₃₁ to R₄₀ are each, independently from one another, hydrogen, deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an amino group, an amidino group, a hydrazine group, a hydrazone group, a carboxylic acid group or a salt thereof, a sulfonic acid group or a salt thereof, a phosphoric acid group or a salt thereof, a C₁-C₂₀ alkyl group, a C₁-C₂₀ alkoxy group, a phenyl group, a biphenyl group, a terphenyl group, a naphthyl group, a fluorenyl group, a spiro-bifluorenyl group, a benzofluorenyl group, a dibenzofluorenyl group, a phenanthrenyl group, an anthracenyl group, a pyrenyl group, a chrysenyl group, a pyridinyl group, a pyrazinyl group, a pyrimidinyl group, a pyridazinyl group, a quinolinyl group, an isoquinolinyl group, a quinoxalinyl group, a quinazolinyl group, a carbazolyl group, a dibenzofuranyl group, a dibenzothiophenyl group, a triazinyl group, a benzimidazolyl group, or a phenanthrolinyl group; a31 to a34 and a38 to a40 are each, independently from one another, an integer from 1 to 5; a35 is an integer from 1 to 7; a36 and a37 are each, independently from one another, an integer from 1 to 4; and * indicates a binding site to an adjacent atom.
 7. The organic light-emitting device of claim 1, wherein two adjacent substituents of R₁ to R₁₄ and R₂₁ to R₂₃ are linked to each other to form a ringed moiety of Formula A:

wherein, in Formula A, Y₁ is NR₄₂, O, or S, R₄₁ and R₄₂ are each, independently from one another, of hydrogen, deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an amino group, an amidino group, a hydrazine group, a hydrazone group, a carboxylic acid group or a salt thereof, a sulfonic acid group or a salt thereof, a phosphoric acid group or a salt thereof, a C₁-C₂₀ alkyl group, a C₁-C₂₀ alkoxy group, a phenyl group, a biphenyl group, a terphenyl group, a naphthyl group, a fluorenyl group, a spiro-bifluorenyl group, a benzofluorenyl group, a dibenzofluorenyl group, a phenanthrenyl group, an anthracenyl group, a pyrenyl group, a chrysenyl group, a pyridinyl group, a pyrazinyl group, a pyrimidinyl group, a pyridazinyl group, a quinolinyl group, an isoquinolinyl group, a quinoxalinyl group, a quinazolinyl group, a carbazolyl group, a dibenzofuranyl group, a dibenzothiophenyl group, a triazinyl group, a benzimidazolyl group, or a phenanthrolinyl group; a41 is an integer from 1 to 4; and * and *′ each indicate a binding site to an adjacent atom.
 8. The organic light-emitting device of claim 1, wherein two adjacent substituents of R₁ to R₁₄ and R₂₁ to R₂₃ are linked to each other to form a ringed moiety of Formula B:

wherein, in Formula B, R₄₃ is hydrogen, deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an amino group, an amidino group, a hydrazine group, a hydrazone group, a carboxylic acid group or a salt thereof, a sulfonic acid group or a salt thereof, a phosphoric acid group or a salt thereof, a C₁-C₂₀ alkyl group, a C₁-C₂₀ alkoxy group, a phenyl group, a biphenyl group, a terphenyl group, a naphthyl group, a fluorenyl group, a spiro-bifluorenyl group, a benzofluorenyl group, a dibenzofluorenyl group, a phenanthrenyl group, an anthracenyl group, a pyrenyl group, a chrysenyl group, a pyridinyl group, a pyrazinyl group, a pyrimidinyl group, a pyridazinyl group, a quinolinyl group, an isoquinolinyl group, a quinoxalinyl group, a quinazolinyl group, a carbazolyl group, a dibenzofuranyl group, a dibenzothiophenyl group, a triazinyl group, a benzimidazolyl group, or a phenanthrolinyl group; a43 is an integer from 1 to 4; and * and *′ each indicate a binding site to an adjacent atom.
 9. The organic light-emitting device of claim 1, wherein the compound represented by Formula 1 is one of the following compounds:


10. The light-emitting device of claim 1, wherein the light-emitting device comprises a capping layer further, and the capping layer has a refractive index of about 1.6 or higher.
 11. The light-emitting device of claim 1, wherein the emission layer comprises a fluorescence emission layer.
 12. The light-emitting device of claim 1, wherein the emission layer comprises the compound of Formula
 1. 13. The light-emitting device of claim 12, wherein the emission layer comprises the compound as a host.
 14. The light-emitting device of claim 12, wherein the emission layer comprises the compound as a dopant.
 15. The light-emitting device of claim 12, wherein the emission layer comprises a phosphorus-containing compound as a host and the compound as a dopant.
 16. The light-emitting device of claim 12, wherein the compound is a thermally activated delayed fluorescence material.
 17. The light-emitting device of claim 1, wherein the first electrode is an anode; the second electrode is a cathode; and the interlayer comprises i) a hole transport region between the first electrode and the emission layer, the hole transport region comprising a hole injection layer, a hole transport layer, a buffer layer, an electron blocking layer, or any combination thereof and ii) an electron transport region between the emission layer and the second electrode, the electron transport region comprising a hole blocking layer, an electron transport layer, an electron injection layer, or any combination thereof.
 18. The light-emitting device of claim 17, wherein the emission layer comprises one phosphorus-containing compound as a host and the compound as a dopant; and the electron transport region comprises another phosphorus-containing compound.
 19. The light-emitting device of claim 18, wherein the one phosphorus-containing compound and the other phosphorus-containing compound are the same compound.
 20. An electronic apparatus comprising: a thin film transistor and the light-emitting device of claim 1, wherein the thin film transistor comprises a source electrode, a drain electrode, an activation layer, and a gate electrode, and the first electrode of the light-emitting device is electrically connected to one of the source electrode and the drain electrode of the thin-film transistor. 